Category 01
Getting started
The vocabulary, the protocols, the providers — everything you need to know before you send your first message.
Knowledge base
Find answers to everything our customers ask.
The vocabulary, the protocols, the regulations, the pricing models — every concept behind A2P messaging, written without marketing fluff. Built from the questions engineering, product, and finance teams ask us every week.
Library at a glance
- 270
- Answers & glossary entries
- 5
- Glossary categories
- 23
- Years of MENA expertise
- 200+
- Countries covered
Written by the BroadNet platform team. No marketing fluff. Updated when the standards change.
Answers
The knowledge behind the network.
Plain-language answers on A2P messaging, SMPP, SS7, RCS, and the regulations that govern them — written by the people who actually run the routes.
200+
countries
1,000+
operator connections
ISO 27001
certified
Browse by topic
Eight categories. One vocabulary.
Each category collects the three to five questions our customers ask most — the ones that come up on every onboarding call, in every procurement review, and on every first integration. Skim a category or jump to a specific answer.
Category 02
SMS API
How A2P SMS actually moves between an application, a CPaaS, an SMSC, and a handset — and the protocols underneath.
Category 03
WhatsApp Business
BSPs, templates, per-message pricing, and the 24-hour window — what makes WhatsApp different from every other channel.
Category 04
RCS
Rich Communication Services explained — verified senders, rich cards, fallback to SMS, and where it sits next to WhatsApp.
Category 05
OTP & Verify
One-time passwords, two-factor authentication, and channel failover — the building blocks of login security.
Category 06
Compliance
Grey routes, SMS firewalls, GSMA IR.71 — the regulatory and security frame around enterprise messaging.
Category 07
Billing
How SMS and WhatsApp are priced, how WhatsApp template messages are charged, and the cost difference between routes.
Category 08
Integrations
REST vs SMPP, what a CPaaS replaces, and how messaging integrates with the operator side of the network.
Full glossary
What does the BroadNet glossary cover?
270 terms in five categories — fundamentals, protocols, regulation, operations, and commercial — each one written for the buyer reading on a Tuesday afternoon trying to evaluate vendors. Concrete numbers, real regulator names, real protocol versions.
Fundamentals87 terms
The core vocabulary of business messaging — A2P, P2P, MO/MT, DLR, OTP, HLR Lookup, MNP, RCS, WhatsApp Business API, Flash Call.
A2P vs bulk SMS — what's the difference?
A2P SMS and bulk SMS overlap but are not the same thing: A2P (application-to-person) describes who sends a message — a software application reaching a person with an OTP, alert, or notification — while bulk SMS describes how you send — one message pushed to many recipients at once, almost always for marketing. All bulk SMS is A2P, but not all A2P is bulk.
A2P vs P2P SMS — what's the difference?
P2P (person-to-person) SMS is one mobile subscriber texting another from their dial-pad. A2P (application-to-person) SMS is a software application messaging a subscriber — OTPs, alerts, notifications, marketing. They look identical on the handset, but underneath they use different operator agreements, different routes, different rate structures, and different regulatory regimes. Sending A2P traffic over P2P routes is exactly what grey-route fraud is, and it is why operators deploy SMS firewalls.
Does the iPhone support RCS?
Yes — the iPhone supports RCS. Apple added RCS Universal Profile support in iOS 18, released in September 2024, so any iPhone running iOS 18 or later can send and receive RCS in the native Messages app when the recipient and both carriers also support it. Before iOS 18, iPhones fell back to SMS and MMS for messages to non-iMessage users.
EID — the eUICC identifier, explained
EID (eUICC Identifier) is the globally-unique 32-digit numeric serial number burned into every eUICC at manufacture. It identifies the secure element across its lifetime — through every operator change, every profile install, every device repurpose. EID is to eUICC what ICCID is to a classic SIM, but it is bound to the chip, not to any single operator's subscription.
eUICC — the embedded UICC chip explained
An eUICC (embedded Universal Integrated Circuit Card) is the soldered-down successor to the removable plastic SIM card. Physically it is a tamper-resistant secure element on the device PCB. Functionally it can hold multiple operator profiles simultaneously, switch between them remotely (Remote SIM Provisioning), and run JavaCard applets. eUICC is the hardware foundation that makes consumer eSIM (SGP.22) and IoT eSIM (SGP.32) possible.
GSM 7-bit vs UCS-2 encoding — when each is used
An SMS body can be encoded in GSM 7-bit (160 characters per segment, covers ASCII plus a small extension table) or UCS-2 (70 characters per segment, covers any Unicode codepoint including Arabic, Chinese, emoji). The choice happens automatically — your aggregator scans the body and picks the narrowest encoding that fits. Mixed encoding is not allowed within a single SMS; one non-GSM-7 character forces the whole message to UCS-2.
HLR lookup vs MNP — what's the difference?
An HLR lookup and MNP are two sides of number intelligence: an HLR (Home Location Register) lookup queries a mobile network over SS7 to confirm whether a number is live and which operator now serves it, while MNP (mobile number portability) is the rule that lets subscribers keep their number when switching operator. Because ported numbers break the old prefix-to-operator mapping, an HLR lookup is how you find a number's real current network.
How do you use SMS for two-factor authentication?
SMS two-factor authentication (2FA) adds a second check to a login by sending a one-time passcode to the user's phone, which they enter alongside their password. It is the most widely deployed 2FA method because it works on any phone with no app, though for high-assurance flows it is increasingly paired with or replaced by phishing-resistant methods. Deliver it over direct routes with rate limiting and short expiry.
How does conversational AI for voice work?
Conversational AI for voice — a voice bot or AI voice agent — lets callers speak naturally to software that understands intent and responds in real time. It chains speech-to-text, a language-understanding or LLM layer, dialogue logic, and text-to-speech over a programmable voice call, so routine contacts are handled end to end without a human agent while complex ones escalate cleanly.
How does HLR lookup and MNP number intelligence work?
HLR lookup and MNP (mobile number portability) intelligence is real-time number validation that queries the Home Location Register over SS7 to confirm whether a number is active, which operator currently owns it after any porting, and whether it is roaming — all before you send. It removes invalid numbers, corrects routing for ported numbers, and cuts wasted A2P spend and fraud exposure.
How does number verification (OTP and 2FA) work?
Number verification confirms that a user actually controls a given phone number — the core of OTP and two-factor authentication. It spans SMS OTP, voice OTP, WhatsApp OTP, flash-call verification, and silent network authentication (a data-session check against the operator with no code to type). Coverage, deliverability, latency, and anti-fraud screening decide which method fits which market.
How does programmable voice work?
Programmable voice is a cloud API that lets applications place, receive, and control phone calls in code — building IVR menus, click-to-call, call tracking, and voice OTP without owning telephony hardware. Calls terminate to any PSTN or mobile number over the same carrier interconnects that carry SMS, and the call flow is driven in real time by API callbacks as the call progresses.
How does RCS Business Messaging work?
RCS Business Messaging (RBM) is the GSMA Universal Profile channel that lets a verified brand send rich, interactive messages — a logo, verified sender name, rich cards, carousels, suggested replies, and read receipts — to the native Messages app on Android and, since iOS 18 (2024), iPhone. It upgrades SMS to an app-like experience without the recipient installing anything.
MO vs MT — what's the difference?
MT (mobile-terminated) is a message destined for a handset — the operator's network is the destination. MO (mobile-originated) is a message sent from a handset — the operator's network is the source. From an enterprise perspective, every A2P SMS you send is MT, and every reply or inbound keyword (STOP, START, HELP) you receive is MO.
OTP vs 2FA — what's the difference?
An OTP (one-time password) and 2FA (two-factor authentication) are related but not the same: an OTP is a single-use code, while 2FA is the security model that requires two independent proofs of identity. An OTP is one common way to deliver the second factor, but 2FA can also use authenticator apps, security keys, or biometrics. OTP is a tool; 2FA is the goal.
RCS vs MMS — what's the difference?
MMS is the legacy multimedia messaging standard that attaches an image, audio, or video to a message over the carrier network; RCS Business Messaging is the modern successor that adds verified branding, interactive cards and buttons, suggested replies, and delivery and read receipts. MMS works on almost any phone as a heavier paid message; RCS works on supported Android and iOS 18+ devices and is far richer, with SMS/MMS as the fallback.
RCS vs SMS — compared
SMS is the 1980s text-only bearer: 160 GSM-7 characters per segment, no media, no branding, delivered over the signalling channel to literally every mobile phone on Earth. RCS Business Messaging (RBM) is the GSMA's modern replacement carried over data: multi-thousand-character messages, rich cards and carousels, a verified branded sender with your logo and name, read receipts, typing indicators and suggested replies. SMS reaches everyone with a phone; RCS reaches modern Android (Universal Profile since 2019) and iPhone (iOS 18, 2024) — and falls back to SMS when RCS is unavailable.
RCS vs WhatsApp — compared
Both are branded, interactive business messaging that beat plain SMS on engagement — but they are architecturally opposite. RCS is a carrier network protocol (GSMA Universal Profile) delivered into the phone's native Messages app, with no app to install. WhatsApp is a Meta over-the-top application installed by 2B+ users worldwide, billed per delivered template message. RCS wins on frictionless native reach and in markets where WhatsApp faces restrictions; WhatsApp wins on installed-base depth, richer media, groups, and mature conversational commerce.
Short code vs long code — when to use each
A short code is a 3-6 digit number leased from a country regulator/operator for high-volume A2P SMS (typically marketing campaigns, voting, donations). A long code is a regular 10-12 digit MSISDN used for two-way conversational SMS or low-volume A2P. They differ in cost, throughput, MO capability, and consumer recognition.
SMS OTP or an authenticator app — which should I use?
Use both, for different jobs. An authenticator app is the stronger factor and cannot be intercepted by a SIM swap, but it requires the user to install and enrol something. SMS OTP is weaker but reaches any handset in any market with nothing installed, which is why it remains the only option that works for every user you have.
SMS vs RCS for OTP — which should you use?
Use SMS for OTP as the universal baseline — it reaches any handset with no app and remains the standard for one-time codes. RCS can carry a verified, branded OTP with a better anti-phishing signal on capable devices, but its reach is not yet universal, so it works best as an enhancement with SMS underneath. For most verification flows in 2026, SMS (or a network check) delivers the code and RCS is optional polish.
The WhatsApp 24-hour window explained
When a customer messages your WhatsApp Business number, you can reply freely with Service-category messages for the next 24 hours; from 1 October 2026 Meta bills service replies per message after a free tier of 1,000 service messages per business phone number per month. After the 24-hour window closes, you must use a pre-approved template (a Marketing, Utility or Authentication message, billed per delivered message) to re-initiate.
Two-factor authentication vs multi-factor authentication — what's the difference?
Two-factor authentication (2FA) requires exactly two independent factors to verify identity; multi-factor authentication (MFA) requires two or more. So 2FA is a specific case of MFA. Both combine factor types — something you know (password), something you have (a phone or passkey), something you are (biometric) — and messaging channels commonly deliver the 'something you have' factor as an OTP or a network check.
UCS-2 — Unicode SMS encoding explained
UCS-2 is the 16-bit Unicode encoding used by SMS when the message body contains any character that is not in the GSM 7-bit alphabet. Arabic, Chinese, Cyrillic, Vietnamese, emoji, and curly quotes all force a message to UCS-2. The trade-off: a UCS-2 SMS carries only 70 characters per segment (vs 160 for GSM 7-bit) — so a 150-character Arabic message costs three billable segments where the same-length English message costs one.
UDH — User Data Header in SMS explained
UDH (User Data Header) is the 6-byte (or longer) prefix attached to the body of an SMS to carry control information — most importantly the concatenation header that tells the recipient handset how to stitch a multi-part long SMS back together. UDH is also how WAP push, OTA SIM update messages, and binary SMS payloads are framed. Without UDH, SMS would have remained a strictly 160-character protocol.
What are WhatsApp Flows?
WhatsApp Flows are interactive, multi-screen forms that a business sends inside a WhatsApp chat — to book an appointment, capture a lead or complete a sign-up — so the customer fills in structured fields without leaving the conversation or opening a website.
What do SMS message statuses mean?
An SMS message moves through statuses on its way to a handset — typically queued or accepted (received by the platform), sent (handed to the operator), delivered (confirmed on the handset), and failed, expired, or rejected when something goes wrong. These states come back as delivery receipts (DLRs), and reading them by status and error code is how you know what actually happened to each message.
What is 2FA (two-factor authentication)?
Two-factor authentication (2FA) requires a user to prove their identity with two independent factors before access is granted — typically something they know (a password) and something they have (a phone receiving an OTP). SMS OTP is the most widely deployed second factor in the world. 2FA sharply reduces account-takeover risk, because a stolen password alone is no longer enough to log in.
What is a concatenated SMS?
A concatenated (or multipart) SMS is a message longer than a single segment — 160 GSM-7 characters, or 70 in UCS-2 — split across multiple SMS parts and reassembled into one message on the handset. A User Data Header (UDH) in each part carries a reference number and sequence so the phone stitches them in order. Concatenation reduces the per-segment payload to 153/67 characters to make room for the UDH, and each part is billed separately. See /answers/what-is-udh-sms, /answers/what-is-encoding-gsm-7-ucs-2, and /tools/sms-segment-calculator.
What is a DID (Direct Inward Dialing) number?
A DID (Direct Inward Dialing) number — also called a virtual or direct-dial number — is a phone number that routes inbound calls (and often SMS) straight to a specific endpoint such as an IVR, an agent, or an application, without a dedicated physical line per number. In programmable voice, DIDs are rented per number per month and provisioned in code to receive calls or two-way messages. See /answers/what-is-ivr and /products/voice.
What is a DLR (Delivery Receipt)?
A DLR is the asynchronous confirmation that an SMS has been delivered (or failed to deliver) at the handset. It is generated by the recipient operator's SMSC, returned over SMPP via deliver_sm or HTTP webhook, and carries a state (DELIVRD, UNDELIV, REJECTD, EXPIRED) plus an operator-specific error code.
What is a flash SMS?
A flash SMS (class 0 message) is a text that appears immediately on the recipient's screen without being saved to the inbox by default, so it demands instant attention and disappears unless the user chooses to keep it. It is used for urgent, ephemeral alerts — critical security warnings, emergency notifications, or attention-grabbing prompts — where an ordinary inbox message might be missed or where you do not want the content stored.
What is a long code?
A long code is a standard-length E.164 phone number — a virtual mobile or geographic number — used to send and receive SMS. Unlike a short code it supports two-way conversational messaging and is quick and cheap to provision, but has lower throughput and, on unregistered routes, weaker deliverability. In the United States, A2P long-code traffic must be registered as 10DLC. See /answers/what-is-short-code and /answers/what-is-short-code-vs-long-code.
What is a messaging platform?
A messaging platform is software that lets a business send and receive messages across channels — SMS, WhatsApp, RCS, voice, email — through one system, typically with APIs, routing, delivery tracking, and often campaign and automation tooling. It sits between your applications and the mobile networks, so you build once and reach customers on any channel rather than integrating each operator and app yourself.
What is a notification API?
A notification API is a programmatic interface that lets an application send notifications to users across channels — SMS, WhatsApp, RCS, voice, email, push — from a single integration. It abstracts each channel's delivery mechanics so your software can trigger a message with one call, and increasingly it orchestrates channel choice and fallback so a notification reliably reaches the user.
What is a number lookup API?
A number lookup API returns intelligence about a phone number in real time — whether it is valid and active, which country and operator it belongs to, whether it has been ported, and its line type. It queries the operator's HLR (or a number-intelligence database) so you can clean lists, route correctly, price accurately, and screen for fraud before you spend on a message or a call.
What is a sender ID?
A sender ID is the 'from' identity a recipient sees on an A2P SMS. It can be an alphanumeric string (up to 11 GSM-7 characters, typically a brand name), a numeric long code, or a short code. Alphanumeric sender IDs let brands show a recognisable name instead of a number, but most countries require them to be pre-registered with the regulator or operator before traffic will deliver.
What is a verification flow?
A verification flow is the end-to-end process that confirms a user controls a phone number or identity — requesting a factor, delivering it over one or more channels, collecting the user's response, and confirming or rejecting it. Modern flows are multi-channel and risk-aware: they cascade methods (network authentication, SMS, voice) so a single failed channel never blocks a legitimate user.
What is a verified sender?
A verified sender is a business messaging identity that a channel has authenticated and bound to a real brand — an RCS/RBM verified agent with logo and checkmark, a verified WhatsApp Business, or a registered SMS sender ID. Verification proves the message genuinely comes from the brand, closing the sender-ID spoofing gap that makes unauthenticated SMS a smishing vector. It is central to both trust and A2P monetization. See /answers/rcs-business-messaging, /answers/what-is-sender-id-spoofing, and /answers/what-is-smishing.
What is a WhatsApp BSP?
A WhatsApp Business Solution Provider (BSP) is a Meta-approved partner that hosts enterprise access to the WhatsApp Business API. Businesses can also connect directly through Meta's Cloud API, but most work through a BSP for onboarding, template approval, verification, billing and support. BroadNet is an official Meta BSP.
What is a WhatsApp template message?
A WhatsApp template message is a pre-approved, reusable message format that businesses must use to initiate a conversation or message a user outside the 24-hour service window. Templates are submitted to Meta for review, categorized as Utility, Authentication, or Marketing, and can include variables, buttons, and media — they are how you proactively reach customers on WhatsApp in a permission-based way.
What is A2P SMS?
A2P (application-to-person) SMS is a text message initiated by a business software application — for OTPs, notifications, alerts, transactional confirmations, marketing — delivered to a consumer mobile phone. A2P is the dominant business-messaging modality globally, with over 2 trillion A2P messages sent per year.
What is an HLR (Home Location Register)?
The HLR (Home Location Register) is the central subscriber database in a 2G/3G mobile network. It stores each subscriber's MSISDN, IMSI, service entitlements, and the address of the MSC/VLR currently serving them. When an SMS arrives, the destination operator's SMSC queries the HLR over SS7 MAP (SendRoutingInfoForSM) to locate the subscriber before delivery. In 4G/5G the HSS — and later the 5G UDM — replaces it. The HLR is the network element itself; querying it from outside the operator is a separate service, HLR Lookup — see /answers/what-is-hlr-lookup.
What is an IMEI?
IMEI (International Mobile Equipment Identity) is the 15-digit serial number that identifies a physical handset, not the subscriber. Where the IMSI identifies the SIM and the MSISDN is the phone number, the IMEI identifies the device itself. Operators use it to block stolen handsets through the EIR (Equipment Identity Register) and to enforce device-based policy. It plays no direct role in SMS routing but often appears alongside the IMSI in fraud analysis.
What is an IMSI?
IMSI (International Mobile Subscriber Identity) is the globally unique identifier a mobile network uses to recognise a subscriber. Stored on the SIM/eUICC and in the HLR/HSS, it is up to 15 digits: a Mobile Country Code (MCC), a Mobile Network Code (MNC), and a subscriber identity (MSIN). Unlike the MSISDN — the dialable phone number — the IMSI lives on the signalling plane and is never exposed to other subscribers.
What is an MMSC (Multimedia Messaging Service Centre)?
An MMSC is the operator infrastructure node that stores, transcodes, and forwards MMS messages — picture messages, video, audio, and rich text larger than the SMS 160-character limit. Every MMS sent or received on a 2G/3G/4G mobile network is brokered by an MMSC, the multimedia equivalent of the SMSC.
What is an MSISDN?
MSISDN (Mobile Subscriber ISDN Number) is the technical name for a phone number — the E.164-formatted number (country code plus national subscriber number, up to 15 digits) used to route calls and SMS to a subscriber. It is the value you put in the `to` field of an SMS API call. The MSISDN is distinct from the IMSI, the internal SIM identifier the network uses on the signalling plane and never exposes to other subscribers.
What is an SMS aggregator?
An SMS aggregator is a company that connects to mobile operators and resells that connectivity to businesses, so enterprises can reach many networks through one relationship instead of contracting each operator. Aggregators route A2P traffic, handle sender-ID and compliance, and pass back delivery receipts. The key distinction is whether an aggregator holds direct operator agreements or resells another party's routes.
What is an SMS API?
An SMS API is a REST or SMPP endpoint that enterprise applications call to send SMS messages programmatically. It abstracts the SMSC, the operator connections, the SS7 signalling, and the regulatory compliance — exposing a simple POST /messages or SMPP submit_sm command.
What is an SMS gateway?
An SMS gateway is the system that connects applications to mobile networks so software can send and receive SMS — translating an API or SMPP request into the operator protocols that deliver a message to a handset, and passing delivery receipts and inbound messages back. It abstracts the SMSC connections, routing, and signalling so you integrate once instead of connecting to every operator yourself.
What is an SMS short code?
A short code is a special 3-8 digit number, shorter than a full phone number, leased for high-throughput A2P and P2A SMS — marketing campaigns, keyword opt-ins, and two-way programmes. Short codes are provisioned per country, approved by operators, and carry the highest send rates and best deliverability, but cost more and take weeks to activate. See the fuller comparison at /answers/what-is-short-code-vs-long-code and /answers/what-is-long-code.
What is an SMS short link?
An SMS short link is a shortened, often branded URL used in a text message to save characters and track clicks. Because SMS is billed per segment, a long URL can push a message into a second segment; a short link keeps it compact, and a branded domain keeps it trustworthy. Link analytics then tell you how many recipients clicked — the closest thing SMS has to an engagement metric.
What is ANI (Automatic Number Identification)?
ANI (Automatic Number Identification) is a telephony feature that identifies the originating/billing number of a caller and passes it to the receiving end. Originating in the North American PSTN, ANI is often used interchangeably with CLI, but they differ: ANI reflects the billing line and is harder to alter, while CLI (caller ID) is the display number the callee sees and can be spoofed. See /answers/what-is-cli and /answers/what-is-did.
What is bulk messaging?
Bulk messaging is sending a large volume of messages — SMS or another channel — to many recipients at once, for alerts, notifications, or marketing campaigns. It depends on a consented list, a registered sender ID, correct encoding to control cost, adequate throughput, and delivery-receipt monitoring. The scale is what makes list quality and route quality matter: small per-message problems multiply across a large send.
What is channel fallback?
Channel fallback is automatically re-sending a message on a second channel when the first fails to deliver or is unavailable — for example WhatsApp or RCS first, then SMS. It maximizes the chance the message reaches the recipient by pairing a rich, preferred channel with a universal one underneath, and is the mechanism that lets omnichannel messaging combine richness with reliability.
What is CLI (Calling Line Identification)?
CLI (Calling Line Identification) is the telephone number presented to the called party as the origin of a call — the voice-network equivalent of an SMS sender ID. It is carried in call signaling (SS7 IAM, or SIP From / P-Asserted-Identity). CLI can be legitimately set — a business showing its main number — or fraudulently spoofed, which is exactly why authentication frameworks like STIR/SHAKEN exist. See /answers/what-is-ani, /answers/what-is-stir-shaken, and /answers/what-is-did.
What is DTMF?
DTMF (Dual-Tone Multi-Frequency) is the signaling produced when a caller presses a phone keypad — each digit is a pair of audio tones the network decodes. It is how callers navigate IVR menus ('press 1 for sales') and enter data like account numbers or a voice-OTP confirmation. In VoIP, DTMF is commonly sent out-of-band (RFC 2833 / telephone-event) rather than as in-band audio, so it survives compression. See /answers/what-is-ivr and /answers/programmable-voice.
What is E.164?
E.164 is the ITU-T international public telecommunication numbering plan — the worldwide standard format for phone numbers. An E.164 number is a country code followed by a national subscriber number, up to 15 digits total, written with a leading '+' (for example +9714XXXXXXX). Every MSISDN follows E.164. Passing numbers in strict E.164 form is the single most reliable way to avoid routing and delivery failures on an A2P SMS API.
What is Flash Call verification?
Flash Call is a number-verification technique that places a missed call to the user's phone with a one-time short MSISDN as the caller-ID. The user's app reads the last 4-6 digits of the incoming caller-ID — that is the OTP — and the call is hung up before it rings. The user sees nothing; the verification completes silently. It is faster, cheaper, and harder to spoof than SMS OTP.
What is GSM-7 encoding?
GSM-7 is the default 7-bit character encoding for SMS, defined in 3GPP TS 23.038. It covers the basic Latin alphabet, digits, and punctuation — roughly 128 characters — and fits 160 characters into a single SMS segment. Any character outside the GSM-7 set (emoji, Arabic, Cyrillic, accented Latin such as é or ñ) forces the whole message into UCS-2, which drops the limit to 70 characters per segment.
What is HLR Lookup?
An HLR (Home Location Register) lookup is a real-time query against a mobile operator's subscriber database that returns whether a number is active, who owns it today (the original operator if ported, the current operator if not), what country it terminates in, and whether the subscriber is currently roaming. It is the single most useful number-quality check before sending an SMS.
What is inbound SMS?
Inbound SMS — also called mobile-originated (MO) SMS — is a message sent by a person to your business number, such as a reply, a keyword, or a STOP request. It arrives at your application through a webhook and is the foundation of two-way messaging: confirmations, support conversations, surveys, keyword campaigns, and opt-out handling all depend on receiving inbound messages.
What is IVR (Interactive Voice Response)?
IVR (Interactive Voice Response) is an automated telephony system that plays voice prompts and collects caller input via keypad (DTMF) tones or speech recognition, then routes the call or serves information without a human agent. Programmable-voice IVR flows are built in code — 'press 1 for sales' menus, self-service balance checks, or voice-OTP delivery. See /answers/what-is-acd, /answers/what-is-did, /products/voice, and /products/voice.
What is MMS (Multimedia Messaging Service)?
MMS (Multimedia Messaging Service) is the carrier messaging standard that extends SMS to carry images, audio, video, and longer text. Messages transit an MMSC — rather than an SMSC — and are fetched by the handset over the data network. A2P MMS is used for rich marketing where supported, though RCS Business Messaging and WhatsApp increasingly replace it. See /answers/what-is-mmsc, /answers/what-is-rcs-business-messaging, and /products/mms.
What is MNP (Mobile Number Portability)?
MNP is the regulatory regime that lets a subscriber keep their mobile number when they switch from one operator to another. The number is unchanged; the routing is updated. Every operator maintains a central or per-operator number portability database, queried at call/SMS routing time so the message reaches the new operator's HLR, not the original one.
What is number masking?
Number masking (call and SMS anonymization) uses a temporary proxy number to connect two parties — a rider and driver, a buyer and seller — so neither sees the other's real number. The platform maps both real numbers to the proxy and relays calls and texts through it, protecting privacy and keeping the conversation on-platform for safety and auditability. It is built on DID numbers and programmable voice and SMS. See /answers/what-is-did and /answers/programmable-voice.
What is OTP?
OTP (One-Time Password) is a single-use code sent to a user to verify their identity for login, transaction, or account recovery. OTPs are most commonly delivered via SMS, but also via WhatsApp, email, voice, and authenticator apps. OTP is the most common form of 2FA (two-factor authentication) globally.
What is outbound SMS?
Outbound SMS — also called mobile-terminated (MT) SMS — is a message your business sends to a person's phone, such as an OTP, alert, notification, or marketing message. It is submitted through an SMS API or SMPP, routed to the recipient's operator, and confirmed by a delivery receipt. Most A2P traffic is outbound; pairing it with inbound SMS creates two-way conversations.
What is P2A SMS?
P2A (person-to-application) SMS is a message a mobile subscriber sends from their handset to a business application — texting a keyword like STOP, HELP, BALANCE, or a competition code to a short code or virtual long number. It is the inbound, mobile-originated counterpart to A2P (application-to-person) SMS, and the mechanism behind two-way SMS, opt-in keywords, and conversational campaigns.
What is P2P SMS?
P2P (person-to-person) SMS is a text message sent from one mobile subscriber to another using their handset's native messaging app — the kind of SMS that has existed since 1992. It rides over operator P2P routes, uses the originator's MSISDN as the sender, and is priced inside the consumer's tariff bundle rather than as a commercial event.
What is RCS Business Messaging (RBM)?
RCS Business Messaging is the enterprise variant of RCS — the GSMA-standardised successor to SMS. It lets verified brands send rich cards, carousels, suggested replies, buttons, and read-receipt-trackable content into the recipient's native Messages app, without requiring the user to install anything. RBM is supported on Android via Google Messages and on iPhone since iOS 18 (2024).
What is RCS for business (RBM)?
RCS Business Messaging (RBM) lets brands send verified, richly formatted messages straight to the native Messages app — a branded sender with logo and verified checkmark, image cards, carousels, suggested-reply and suggested-action buttons, plus delivery and read receipts and analytics. It is the natural upgrade from SMS on supported devices, with SMS remaining the fallback where RCS isn't available. See /products/rcs-messaging.
What is RCS MaaP (Messaging as a Platform)?
RCS MaaP (Messaging as a Platform) is the GSMA architecture that lets brands and chatbots reach subscribers over RCS through the carrier's messaging platform. MaaP hosts business agents, applies verification, and connects them to the RCS network, so an aggregator or brand integrates once to reach every subscriber on that platform. It is the plumbing behind RCS Business Messaging — the layer where verified agents, bots, and rich-card content are managed. See /answers/rcs-business-messaging and /answers/what-is-rcs-business-messaging.
What is RCS?
RCS (Rich Communication Services) is the modern replacement for SMS — a protocol that supports verified branded senders, rich cards, suggested replies, read receipts, and group messaging. RCS Business Messaging (RBM) is the enterprise variant. Native in Android Messages since 2019; supported on iPhone since iOS 18 (2024).
What is rich card messaging?
Rich card messaging sends a visually formatted card — an image or media, a title and description, and tappable buttons or suggested actions — instead of plain text, on channels like RCS and WhatsApp. Cards turn a notification into an interactive unit: a product with a Buy button, an order with a Track button, a booking with Confirm and Reschedule — driving action inside the message thread.
What is silent network authentication?
Silent network authentication (SNA) verifies a phone number by checking it directly against the mobile operator's network over the device's data connection, instead of sending an SMS one-time password. The user types nothing and sees no code — the operator confirms the SIM in the device matches the number claimed. It is fast, invisible, and resistant to the phishing and SMS-pumping fraud that plague SMS OTP.
What is the PSTN?
The PSTN (Public Switched Telephone Network) is the traditional circuit-switched telephone network of landlines, exchanges, and interconnects that predates VoIP. Programmable voice and SIP trunking reach it through PSTN termination and origination, so a call placed by an API can ring any ordinary phone number and inbound calls from landlines can reach an application. Much of the PSTN core is now IP, but the numbering plan and reach it represents remain central to voice. See /answers/voice-api-sip-trunking, /answers/what-is-did, and /products/voice.
What is the SMS character limit?
A single SMS holds 160 characters in the GSM-7 alphabet, or 70 characters if the message contains any Unicode (UCS-2) character such as an emoji or a non-Latin script. Longer messages are split into concatenated segments of 153 GSM-7 characters (or 67 Unicode characters) each, because a header is reserved to reassemble them — and every segment is billed separately.
What is the SMS validity period?
The validity period is how long an SMSC will keep retrying delivery of a message that didn't reach the handset on first attempt — typically because the recipient was off-network, out of coverage, or had a full inbox. After the validity period expires, the SMSC drops the message and emits an EXPIRED DLR. Default is usually 24 hours; the SMPP submit_sm validity_period field lets you override.
What is the WhatsApp green tick (verified badge)?
The WhatsApp green tick is the official verified badge Meta grants to a business's WhatsApp account, shown next to the business name to confirm it is authentic and notable. It raises customer trust and reduces impersonation, and is granted by Meta based on the brand's notability and policy compliance — applied for through your Business Solution Provider, not bought.
What is toll-free SMS?
Toll-free SMS is A2P text messaging sent from a toll-free number (in North America, the 800/888/877-style numbers). Toll-free numbers can send and receive SMS at higher throughput than an ordinary long code once verified, and are a common choice for two-way business messaging in the US and Canada. They require verification to send at scale and sit between a long code and a short code in cost and capacity.
What is transactional SMS?
Transactional SMS is a message triggered by a user's action or account and essential to a service — an OTP, an order confirmation, a fraud alert, a delivery update. It carries no marketing, is usually exempt from marketing-consent rules (though still regulated), and is routed on high-priority, reliable paths because its value depends on arriving immediately. It is the opposite of promotional SMS.
What is two-way messaging?
Two-way messaging is SMS (or another channel) that both sends to and receives replies from a recipient, so a customer can text back to confirm, opt out, ask a question, or trigger an action. It requires a number capable of receiving inbound messages — a long code, short code, or toll-free number — and a webhook to route replies into your application in real time.
What is voice broadcast?
Voice broadcast is the automated delivery of a pre-recorded or text-to-speech voice message to many recipients at once — used for alerts, reminders, notifications, and surveys. It reaches people who may not read a text, works on landlines and feature phones, and can collect responses via keypad (DTMF), making it a useful complement to SMS for urgent or accessibility-sensitive communications.
What is voice OTP?
Voice OTP delivers a one-time passcode as an automated phone call that reads the code aloud, rather than as a text message. It is used as a fallback when SMS is undelivered or unsupported, for landlines and feature phones, and for accessibility — ensuring a user can still verify when a text cannot reach them. It is a core part of a resilient, multi-channel verification flow.
What is WhatsApp Business API?
WhatsApp Business API is Meta's enterprise messaging product — a programmatic interface for businesses with more than a few hundred customer conversations per day. Unlike the free WhatsApp Business app (designed for SMEs), the API has no UI: you integrate it into your CRM, support desk, or in-house systems via a Meta-approved Business Solution Provider (BSP).
WhatsApp Cloud API vs On-Premises API: what changed?
The Cloud API is the version of the WhatsApp Business Platform API that Meta hosts; the On-Premises API was the older version that a business or its provider ran on its own servers. Meta has retired the On-Premises API — its final version expired on 23 October 2025 — so new integrations use the Cloud API. BroadNet, an official Meta Business Solution Provider, onboards customers directly onto the Cloud API.
Protocols & standards55 terms
The wire and the spec — SMPP 3.4 vs 5.0, SS7 MAP, Diameter S6a, GSMA IR.71 testing, FS.07/FS.11 signalling firewalls, SGP.32 eSIM, SAS-SM, TLS 1.3, HMAC-SHA256, REST vs SMPP.
Diameter S6a — the 4G equivalent of MAP
Diameter S6a is the 3GPP-defined interface between a 4G MME (Mobility Management Entity) and an HSS (Home Subscriber Server). It carries authentication vectors, location updates, and — relevant for messaging — the Send-Routing-Info-for-SM equivalent used when SMS is delivered via SGs or SMS-over-IP. Diameter is to 4G what SS7 MAP is to 2G/3G.
eSIM ES interfaces — ES2+, ES8+, ES9+, ES10 explained
The eSIM ecosystem is held together by a set of ES (eSIM) interfaces defined in GSMA SGP.22 (consumer) and SGP.32 (IoT). Each ES interface specifies who talks to whom, what they exchange, and how it is secured. ES2+ is operator-to-SM-DP+. ES8+ is SM-DP+-to-eUICC over the air. ES9+ is LPA-to-SM-DP+ over HTTPS. ES10 is LPA-to-eUICC inside the device. Knowing these is the difference between reading the spec and reading hieroglyphs.
eUICC security domains — ISD-R, ISD-P, MNO-SD, ECASD
Inside an eUICC, every cryptographic key and every profile is isolated inside a Security Domain — a logical container with its own keys, its own access rules, and its own privileges. The four domains that matter for eSIM Remote SIM Provisioning are ISD-R (the boss), ISD-P (per-profile), MNO-SD (operator OTA), and ECASD (the certificate root). Understanding them is the difference between debugging an eSIM failure in an hour and debugging it in a week.
GSMA FS.07 and FS.11 — the SS7 signalling firewall standards
GSMA FS.07 ("SS7 and Sigtran Network Security") and FS.11 ("SS7 Interconnect Security Monitoring Guidelines") are the two GSMA Permanent Reference Documents that define what a modern SS7 signalling firewall must do. Every operator that wants to be considered for a roaming or A2P agreement with a tier-1 partner must demonstrate FS.07/FS.11 compliance.
GSMA IR.71 explained
GSMA Permanent Reference Document IR.71 — "SMS Network-to-Network Interconnect" — is the GSMA's guidance for monetizing A2P SMS traffic between operators. It defines the commercial framework for A2P route agreements, signalling expectations, anti-abuse measures, and audit trail requirements.
GSMA IR.71 testing — what an A2P route audit looks like
GSMA IR.71 is the GSMA's reference document for A2P SMS network-to-network interconnect. Beyond defining the commercial framework, IR.71 prescribes a testing regime that operators use to validate that an aggregator's route is legitimate, well-formed, and free of grey-route bypass. Passing IR.71 testing is the prerequisite for getting a direct A2P agreement with most tier-1 operators.
GT — Global Title in SS7 routing explained
A Global Title (GT) is an SS7 address — usually a phone number or an E.164-style numeric — used to route SCCP messages between network elements when the sender does not know (or does not want to know) the destination's Point Code. Where Point Codes are network-internal addresses, Global Titles are application-level addresses; the STP translates GT to DPC at routing time. Every MAP query against an HLR uses GT-based routing.
HMAC-SHA256 for DLR webhook signing — how and why
HMAC-SHA256 is the cryptographic primitive every modern messaging platform uses to sign delivery-receipt and inbound-message webhooks. The platform computes a keyed hash over the request body using a shared secret; your endpoint recomputes the same hash and compares. This proves the webhook came from the platform — not from someone who guessed your URL — and that the body was not tampered with in transit.
How does a voice API and SIP trunking work?
A voice API and SIP trunking give applications programmable access to the telephone network over IP. SIP trunking replaces physical phone lines with SIP sessions that carry calls to and from the PSTN and mobile networks; a voice API layers a REST and webhook control surface on top, so software can place, receive, and steer calls in code across 200+ countries.
How does SIGTRAN (SS7 over IP) work?
SIGTRAN is the IETF family of protocols that carries legacy SS7 signaling over IP networks instead of dedicated TDM links. It uses SCTP as a reliable, multi-homed transport and adaptation layers such as M3UA and M2PA to present SS7's MTP interface to IP — letting operators run SS7/MAP interconnects, SMS delivery, and HLR queries across modern packet networks without changing the applications on top.
How does the SMPP protocol work?
SMPP (Short Message Peer-to-Peer) is the open TCP protocol that carries A2P SMS between an application — the ESME — and a mobile operator's SMSC. The ESME opens a persistent bind, submits messages as binary submit_sm PDUs, and receives delivery receipts back over the same socket. Version 3.4 (1999) runs almost every commercial A2P bind today; 5.0 exists but is rarely deployed. SMPP is the high-throughput alternative to a REST SMS API.
Milenage algorithm — 3GPP authentication explained
Milenage is the 3GPP-standardised authentication and key-generation algorithm that every GSM/UMTS/LTE network uses to verify a subscriber and derive session keys. It runs inside the SIM/eUICC and inside the operator's HLR/HSS, taking the subscriber's Ki (long-term key), OPc (operator-customised constant), and a network random challenge (RAND), and producing the response (RES), the ciphering key (CK), the integrity key (IK), and an anonymity key (AK). It is the cryptographic foundation of mobile authentication.
OCS, IN, and INAP — operator real-time charging explained
OCS (Online Charging System), IN (Intelligent Network), and INAP (Intelligent Network Application Protocol) are the operator-side components that decide, in real time, whether a subscriber can complete a call, send an SMS, or use a kilobyte of data — and how much to charge. For prepaid networks they are non-negotiable; for postpaid they are increasingly used for plan policy enforcement.
OPC and DPC — SS7 Point Codes explained
Every SS7 node (STP, HLR, MSC, SMSC, SCP) has a unique numeric address called a Point Code (PC). On every SS7 message, the Originating Point Code (OPC) identifies the sender and the Destination Point Code (DPC) identifies the intended recipient — exactly analogous to IP source and destination addresses, but in the SS7 numbering plan. OPC/DPC routing is the foundation of how SS7 traffic moves between network elements.
SAS-SM certification — what it means for SIM and eSIM trust
SAS-SM is the GSMA's Security Accreditation Scheme for Subscription Management — the audit that any vendor running SM-DP+, SM-SR, or eIM infrastructure must pass to be trusted by mobile operators for eSIM profile provisioning. Without SAS-SM, no tier-1 operator will exchange profile signing keys with you.
SGP.32 — eSIM IoT for M2M without the SM-DP+ dance
SGP.32 is the GSMA's 2023 specification for IoT eSIM provisioning. Where the consumer eSIM spec (SGP.22) requires user interaction with a QR code and the legacy M2M spec (SGP.02) requires a heavyweight SM-DP/SM-SR pair, SGP.32 introduces the IoT Profile Assistant (IPA) and a remote SIM provisioning flow designed for headless devices that ship without a screen.
SIGTRAN — SS7 over IP explained
SIGTRAN is the IETF/3GPP family of protocols that transports SS7 signalling over IP networks (typically over SCTP, not TCP, for ordered multi-streamed reliable delivery). It replaced the dedicated TDM/E1 SS7 links that operators used to lease at huge cost, letting SS7 ride the same IP backbone as everything else. Almost every operator-to-operator SS7 link in 2026 is in fact SIGTRAN underneath.
SIGTRAN adaptation layers — M3UA, M2UA, SUA explained
Inside SIGTRAN, the SS7 application protocols (MAP, ISUP, SCCP) need a bridge to the IP/SCTP transport. That bridge is an adaptation layer. Three are in production use: M2UA (replaces MTP2), M3UA (replaces MTP3), and SUA (SCCP-User Adaptation — bypasses MTP3 entirely and connects SCCP directly to SCTP). Picking the right layer is mostly about how much of the legacy SS7 stack you want to keep.
SM-DP+ — Subscription Manager Data Preparation, explained
SM-DP+ (Subscription Manager — Data Preparation +) is the GSMA-defined server that prepares, encrypts, and securely delivers eSIM profiles to an eUICC. It is the central trust component of the consumer eSIM architecture (GSMA SGP.21/22) and the IoT eSIM architecture (SGP.31/32), holding the operator's profile signing keys inside an HSM and binding each profile to one specific eUICC identifier (EID).
SM-DS — Subscription Manager Discovery Service
SM-DS (Subscription Manager — Discovery Service) is the GSMA-defined directory that lets an eUICC discover that one or more SM-DP+ servers have profile downloads waiting for it, without the user needing to scan a QR code or type an activation code. It is the silent partner of SM-DP+: SM-DP+ holds the profile, SM-DS tells the eUICC where to fetch it.
SMPP 3.4 vs SMPP 5.0 — what changed and what to use
SMPP 3.4 (1999) is still the SMS interconnect protocol that runs almost every A2P bind in production today. SMPP 5.0 (2003) added Unicode-clean headers, broadcast and cell-broadcast support, and TLVs for richer message classes — but most SMSCs and aggregators never moved to it. If you are picking today, bind to SMPP 3.4 over TLS unless your counterparty specifically asks for 5.0.
SMSC vs SMS gateway — what's the difference?
An SMSC and an SMS gateway sit at different layers of the delivery path. An SMSC (Short Message Service Centre) is the store-and-forward node inside a mobile operator's core network that queues and delivers SMS to handsets; an SMS gateway is the application-facing platform that accepts messages over HTTP or SMPP and routes them to the correct operator's SMSC. Every SMS passes through an SMSC; a gateway is how an application reaches one.
SS7 MAP — what it is and why messaging still depends on it
SS7 MAP (Mobile Application Part) is the signalling protocol GSM/UMTS networks use for everything that is not a voice call or data session — location updates, supplementary services, USSD, and the SRI-for-SM / MT-ForwardSM exchange that delivers every SMS to a handset. Even in 2026, every cross-operator SMS in a 2G/3G/4G/5G non-standalone network still terminates through MAP.
TLS 1.3 in messaging — what changed and why it matters for SMPP
TLS 1.3 (RFC 8446, 2018) replaced TLS 1.2 with a faster handshake, removed every algorithm that had been broken in the previous decade, and made forward secrecy mandatory. For messaging, the practical impact is on SMPP bindings: shorter handshake means faster reconnect when an SMSC reboots, and removal of RSA key exchange means a captured pcap of past SMPP traffic cannot be decrypted later even if the private key leaks.
Tuak algorithm — the higher-strength Milenage alternative
Tuak (sometimes written TUAK) is the 3GPP-specified second-generation authentication algorithm for mobile networks, designed as a future-proof alternative to Milenage. Where Milenage is built on AES-128, Tuak is built on the Keccak permutation (the same primitive behind SHA-3), allowing larger key sizes (up to 256 bits) and a different cryptographic family in case AES-based Milenage ever weakens. Tuak is functionally interchangeable with Milenage at the air-interface level — the network selects which to use.
What are MCC and MNC codes?
MCC (Mobile Country Code) and MNC (Mobile Network Code) together identify one mobile network anywhere in the world. The three-digit MCC names the country and the two- or three-digit MNC names the operator within it — MCC 424 is the United Arab Emirates, and 424-02 and 424-03 are e& (Etisalat) and du.
What are voice codecs (G.711, Opus)?
A voice codec encodes analogue speech into digital packets for transport and decodes it back, trading bandwidth against audio quality. G.711 is the classic uncompressed toll-quality codec at ~64 kbit/s, ubiquitous and low-latency but bandwidth-heavy. Opus (RFC 6716) adapts its bitrate dynamically and is highly resilient to packet loss, making it the modern choice for VoIP and WebRTC. Transcoding between codecs on a call path costs quality and adds delay. See /answers/voip-quality, /answers/what-is-webrtc, and /products/voice.
What is a messaging webhook?
A messaging webhook is an HTTPS endpoint on your server that a messaging platform calls to push you real-time events — delivery receipts, inbound (mobile-originated) messages, and status changes — instead of you polling an API for them. It is how your application learns that a message was delivered, failed, or received, the instant it happens, so you can react programmatically.
What is a silent SMS?
A silent SMS — formally a Type 0 short message — is a text that a phone must acknowledge to the network but then discards without displaying it or alerting the user. Networks use it to check that a handset is reachable; it can also be abused to track a device, which is why operators screen unsolicited Type 0 traffic.
What is a VLR (Visitor Location Register)?
The VLR (Visitor Location Register) is a temporary subscriber database attached to each MSC. When a handset camps on an MSC — at home or roaming — the VLR pulls a working copy of that subscriber's profile from the HLR, so the serving network can set up calls and deliver SMS without querying the home HLR every time. It is the local cache to the HLR's system of record.
What is an ESME?
ESME (External Short Messaging Entity) is the SMPP term for any application outside the SMSC that submits or receives SMS. In an A2P deployment your gateway is the ESME, binding to the operator's SMSC over SMPP. An ESME binds in one of three session modes — Transmitter (send-only), Receiver (receive-only), or Transceiver (both directions on one connection, added in SMPP 3.4). Modern deployments almost always use a single Transceiver bind.
What is an HSS (Home Subscriber Server)?
The HSS (Home Subscriber Server) is the central subscriber database of a 4G LTE / IMS core network — the Diameter-based successor to the 2G/3G HLR. It stores subscriber identities, authentication keys, and service profiles, and answers S6a/S6d signaling from the MME during attach and SMS delivery. On 5G standalone its role passes to the UDM. See /answers/what-is-hlr, /answers/diameter-s6a-explained, and /products/hlr-lookup.
What is an MSC (Mobile Switching Centre)?
The MSC (Mobile Switching Centre) is the core 2G/3G network node that switches voice calls and relays SMS for the handsets currently in its coverage area. For a mobile-terminated SMS, the sending SMSC uses SS7 MAP MT-ForwardSM to hand the message to the recipient's serving MSC, which pages the handset and delivers it. Each MSC is paired with a VLR that caches subscriber data for the devices it serves.
What is an MSRN (Mobile Station Roaming Number)?
An MSRN (Mobile Station Roaming Number) is a temporary number the visited network's VLR allocates so an incoming call can be routed to a subscriber's current serving MSC. During call setup the HLR requests it over MAP (Provide-Roaming-Number); the network uses it to route the call, then releases it. It is a routing number, never dialed by a user, and it is how roaming and forwarded calls reach the right switch. See /answers/what-is-vlr, /answers/what-is-hlr, and /answers/ss7-map-explained.
What is an SBC (Session Border Controller)?
An SBC (Session Border Controller) is the security and control element that sits at the edge of a VoIP network, policing SIP signaling and RTP media as they cross between networks. It handles NAT and firewall traversal, hides internal topology, enforces call admission and rate limits, transcodes codecs when two sides differ, and defends against SIP-based attacks and toll fraud. Every serious SIP trunking and voice-API deployment sits behind one. See /answers/what-is-sip, /answers/what-is-nat-traversal, and /answers/voice-api-sip-trunking.
What is an SMSC?
An SMSC (Short Message Service Center) is the core infrastructure component of a mobile network that stores, forwards, and delivers SMS messages between mobile devices and external applications. Every SMS — A2P, P2P, MO, MT — passes through an SMSC.
What is cell broadcast?
Cell broadcast is a mobile network service that sends one message to every handset connected to a chosen set of cell towers at the same moment, without knowing any phone numbers. Authorities use it for public warnings — earthquakes, floods, missing children — because it reaches everyone in an area even when the network is congested.
What is ENUM (E.164 Number Mapping)?
ENUM (E.164 Number Mapping, RFC 6116) is an IETF standard that maps an E.164 phone number to internet resources — SIP URIs, email, web — by encoding the number as a domain name and looking it up in DNS. It lets carriers and enterprises route calls and messages to IP endpoints straight from a phone number, and underpins number portability and VoIP interconnect. See /answers/what-is-e164, /answers/what-is-mnp, and /answers/programmable-voice.
What is GTT (Global Title Translation)?
GTT (Global Title Translation) is the SCCP-layer function that resolves a global title — a network address such as an E.164 or E.214 number — into the point code and subsystem number needed to route SS7 signaling to the right node: an HLR, SMSC, or MSC. Because senders address a global title rather than a physical point code, GTT is where operators (and SS7 firewalls) steer and screen inter-network SMS and MAP signaling. See /answers/ss7-global-title, /answers/what-is-sccp, and /operators/ss7-firewall.
What is IMS (IP Multimedia Subsystem)?
IMS (IP Multimedia Subsystem) is the 3GPP core-network architecture that delivers voice, video and messaging over IP on mobile and fixed networks. It carries VoLTE and 5G voice calls, RCS and SMS over IP, using SIP to set up sessions and Diameter to read subscriber data.
What is M3UA?
M3UA (MTP Level 3 User Adaptation) is a SIGTRAN protocol that carries SS7 MTP3-user signaling — SCCP and ISUP — over IP using SCTP, letting legacy SS7 applications run across modern IP networks without TDM links. It is the transport most operators use to reach SS7/MAP peers today, and the layer an SS7 signaling firewall inspects. See /answers/what-is-sigtran, /answers/sigtran-adaptation-layers, and /answers/what-is-sccp.
What is NAT traversal in VoIP?
NAT traversal is how a VoIP endpoint behind a router (which rewrites private IP addresses) still receives voice media. Because SIP and RTP carry IP addresses inside their payloads, plain NAT breaks the media path; techniques such as STUN, TURN, and ICE — plus a Session Border Controller on the network edge — discover the public address and relay media when needed so audio flows both ways. It is a common cause of one-way-audio faults. See /answers/what-is-sbc, /answers/what-is-webrtc, and /answers/what-is-sip.
What is Remote SIM Provisioning (RSP)?
Remote SIM Provisioning (RSP) is the GSMA architecture that lets an operator download, enable and delete subscriber profiles on an eSIM over the air, instead of shipping a physical SIM card. It is what happens when a user scans an eSIM QR code and the phone joins a new network.
What is RTP (Real-time Transport Protocol)?
RTP (Real-time Transport Protocol, RFC 3550) is the protocol that carries the actual audio and video media of a VoIP call over IP, usually over UDP. While SIP handles call setup, RTP streams the encoded voice packets with sequence numbers and timestamps so the receiver can reorder them and play them back in time. Its companion RTCP reports on jitter and packet loss; SRTP adds encryption. See /answers/what-is-sip, /answers/what-is-srtp, and /answers/voip-quality.
What is SCCP?
SCCP (Signalling Connection Control Part) is the SS7 network-layer protocol that adds global-title routing and subsystem addressing on top of MTP, so signaling can reach nodes — HLRs, MSCs, SMSCs — by global title rather than a fixed point code. TCAP and MAP ride on SCCP, and SCCP-level Global Title translation is where operators and firewalls steer and screen inter-network SMS signaling. See /answers/what-is-tcap, /answers/ss7-global-title, and /answers/what-is-m3ua.
What is SCTP (Stream Control Transmission Protocol)?
SCTP (Stream Control Transmission Protocol, RFC 4960) is the transport-layer protocol that carries SIGTRAN signaling over IP. Unlike TCP it is message-oriented, multi-streamed (so one lost packet does not head-of-line-block the others), and multi-homed (an association spans multiple IP paths for instant failover) — the resilience properties a telecom control plane needs. M3UA and the other SIGTRAN adaptation layers ride on SCTP to move SS7 over IP. See /answers/sigtran-explained, /answers/what-is-m3ua, and /answers/what-is-sigtran.
What is SDP (Session Description Protocol)?
SDP (Session Description Protocol, RFC 8866) is the text format that describes a media session — which codecs, IP addresses, ports, and parameters each side will use. It is not a transport itself; it rides inside SIP (or WebRTC) as an offer/answer exchange, so the two endpoints agree on how to send RTP before the media flows. Codec negotiation and NAT candidate exchange both happen in SDP. See /answers/what-is-sip, /answers/what-is-voice-codec, and /answers/what-is-webrtc.
What is SIP (Session Initiation Protocol)?
SIP (Session Initiation Protocol, RFC 3261) is the signaling protocol that sets up, modifies, and tears down real-time voice and video sessions over IP. It handles the call control — inviting, ringing, answering, and hanging up — while the actual audio travels separately as RTP media negotiated through an SDP offer/answer inside the SIP messages. SIP is the backbone of VoIP, SIP trunking, and programmable voice. See /answers/what-is-rtp, /answers/what-is-sdp, and /answers/voice-api-sip-trunking.
What is SMPP window size?
The window is the number of SMPP PDUs an ESME may have in flight — submitted but not yet acknowledged — on a single bind at any moment. It is the single biggest determinant of the throughput you get from a bind, and the setting most often left at a default that silently caps an integration far below its agreed rate.
What is SMPP?
SMPP (Short Message Peer-to-Peer) is the open-protocol standard for exchanging SMS between SMSCs, ESMEs (External Short Message Entities), and aggregators. Version 3.4 is the most widely deployed; 5.0 adds Unicode-clean headers. BroadNet supports both via plain TCP and TLS.
What is SRTP (Secure RTP)?
SRTP (Secure Real-time Transport Protocol, RFC 3711) is the encrypted profile of RTP: it encrypts and authenticates the voice and video media of a VoIP call so it can't be eavesdropped or tampered with in transit. It is typically paired with SIP over TLS (which protects the signaling) and with DTLS key exchange in WebRTC, giving end-to-end call confidentiality. See /answers/what-is-rtp, /answers/what-is-sip, and /answers/what-is-webrtc.
What is SS7?
SS7 (Signalling System No. 7) is the ITU-T-defined control-plane signalling system that 2G and 3G mobile networks use for call setup, mobility management, and SMS routing. Its layered stack — MTP, SCCP, TCAP, and MAP — carries the SendRoutingInfoForSM and MT-ForwardSM operations that deliver every cross-operator SMS to a handset. On 4G and 5G, Diameter and HTTP/2 signalling take over, but SS7 still underpins the majority of SMS delivered today.
What is TCAP?
TCAP (Transaction Capabilities Application Part) is the SS7 layer that manages request/response dialogues between network nodes, carrying application operations such as MAP on top of SCCP. Every HLR query and MT-ForwardSM that delivers an SMS is a TCAP transaction. Because TCAP wraps the MAP operations attackers abuse, it is a key inspection point for SS7 signaling firewalls. See /answers/what-is-sccp, /answers/ss7-map-explained, and /operators/ss7-firewall.
What is the RCS Universal Profile?
The RCS Universal Profile is the GSMA specification that defines which Rich Communication Services features phones, operator networks and messaging apps must support so that RCS works across all of them. It is the common rulebook behind typing indicators, read receipts, high-resolution media, group chat and RCS Business Messaging.
What is WebRTC?
WebRTC (Web Real-Time Communication) is an open standard that lets browsers and apps exchange real-time audio, video, and data peer-to-peer without a plugin. It bundles media capture, the Opus and VP8/VP9 codecs, encrypted transport (SRTP), and NAT traversal (ICE/STUN/TURN), negotiating sessions with SDP. WebRTC powers in-browser click-to-call, video, and voice-agent experiences, often bridged to SIP and the PSTN by a gateway. See /answers/what-is-sip, /answers/what-is-srtp, and /answers/what-is-nat-traversal.
Regulation & sender-ID25 terms
Sender-ID rules per regulator (TDRA, CST, NTRA, TRC), PDPL KSA, GDPR, HIPAA, GSMA Open Gateway.
GDPR for messaging — what enterprise senders need to know
The General Data Protection Regulation (EU 2016/679) governs every collection and use of personal data of individuals in the EU/EEA, including MSISDNs used for messaging. For business messaging, GDPR matters most in five places: lawful basis, opt-out / right to erasure, cross-border transfers, processor agreements, and data-breach notification. Penalties reach the higher of €20 million or 4% of global annual turnover.
HIPAA for messaging — what healthcare senders need to know
HIPAA (the US Health Insurance Portability and Accountability Act) governs Protected Health Information (PHI) — any information that ties an individual to their medical care. For messaging, HIPAA is triggered the moment your SMS or WhatsApp message conveys PHI (a clinic name, an appointment specialty, a test result, a prescription). The relevant rules are the Privacy Rule, the Security Rule, and the Breach Notification Rule.
How do I handle SMS opt-outs?
Honour opt-outs instantly and permanently: recognize standard keywords like STOP (and localized equivalents), add the number to a suppression list, stop all marketing to it immediately, and confirm the opt-out once. Handling opt-outs correctly is both a legal requirement in most markets and a deliverability protection — repeated messaging to people who opted out damages sender reputation.
How do I register an alphanumeric sender ID?
Most regulators require alphanumeric sender IDs to be pre-registered before any A2P SMS is accepted, so registration is a prerequisite, not an option. The general path is: choose a compliant sender ID (up to 11 GSM-7 characters), submit your brand, use case, and sample content, then wait for regulator/operator review. Requirements and lead times differ by country — see the country guides for the exact process in each market.
PDPL (KSA) — what the Saudi Personal Data Protection Law means for messaging
The Personal Data Protection Law (PDPL) is the Kingdom of Saudi Arabia's comprehensive data-protection framework, in force since 14 September 2023 with full enforcement from September 2024. It governs every collection, use, and cross-border transfer of personal data of individuals in KSA — including the MSISDN you message, the consent record you keep, and where in the world that data is processed.
Sender ID registration in Egypt — the NTRA process
Egypt's NTRA (National Telecommunications Regulatory Authority) requires all A2P SMS sender IDs to be pre-approved and all A2P traffic to terminate through NTRA-licensed local aggregators. There is no grey-route tolerance in Egypt — non-licensed routes are detected and blocked by the operator firewalls within days. Registration takes 10-15 business days.
Sender ID registration in Jordan — the TRC process
Jordan's TRC (Telecommunications Regulatory Commission) requires sender-ID pre-registration for all A2P SMS to Jordanian mobile numbers. Registration is handled by the destination operator (Zain Jordan, Orange Jordan, Umniah) or via a licensed local aggregator. Standard turnaround: 5-7 business days. Cost: JOD 50-100 one-time plus modest annual renewal.
Sender ID registration in Saudi Arabia — the CST process
All A2P SMS to KSA mobile numbers must use a CST-registered alphanumeric sender ID. CST (Communications, Space and Technology Commission) requires submission through a licensed local aggregator. Registration typically takes 5-10 business days. STC, Mobily, and Zain KSA each maintain their own enforcement databases synced from CST.
Sender ID registration in the UAE — the TDRA process
Every alphanumeric sender ID used to send A2P SMS to UAE mobile numbers must be pre-registered with the TDRA (Telecommunications and Digital Government Regulatory Authority). Registration goes through a licensed local aggregator (BroadNet, du, e&), takes 5-7 business days, and costs AED 250 one-time plus AED 500 annually per sender ID.
SMS marketing vs transactional SMS — what's the difference?
Transactional SMS and marketing SMS are both A2P, but regulators and carriers treat them very differently. Transactional SMS delivers information a user requested or needs — OTPs, order updates, appointment reminders — and can generally be sent without marketing consent; marketing SMS promotes offers and requires explicit opt-in and a working opt-out. They also differ on timing windows, sender IDs, and routing priority.
What are SMS opt-in best practices?
Collect explicit, informed opt-in before sending marketing SMS: tell subscribers what they are signing up for, how often you will message, and how to stop; keep an auditable record of when and how consent was given; and confirm the subscription with a single welcome message. Clean, consented opt-in is the foundation of both compliance and deliverability — bought or scraped lists fail on both.
What are SMS quiet hours?
Quiet hours are the periods when a market forbids or restricts commercial messaging — typically overnight, sometimes also on religious or national holidays. The window is set per country by the regulator or the operators, applies to the recipient's local time, and usually exempts transactional traffic such as one-time passcodes.
What are SMS sender ID best practices?
Register alphanumeric sender IDs in every market that requires it, keep the ID to a recognizable brand name (up to 11 GSM-7 characters), classify traffic correctly as transactional or promotional, use it consistently so customers learn to trust it, and never send content that contradicts the registered use case. A well-managed sender ID lifts trust and delivery; a mismatched one gets suspended by the operator firewall.
What are the WhatsApp opt-in rules?
WhatsApp requires a business to get a person's opt-in before messaging them through the WhatsApp Business Platform. Under Meta's policy the opt-in must make clear that the person agrees to receive messages from your business and must name your business; you choose how to collect it, and you must also meet the consent laws of every country you send to. BroadNet, an official Meta Business Solution Provider, sets up opt-in and opt-out handling as part of WhatsApp onboarding.
What is a DNC (Do Not Call) list?
A DNC (Do Not Call) list — also called Do Not Disturb (DND) in some markets — is a register of phone numbers whose owners have opted out of marketing calls or messages. Many regulators run national DNC/DND registries, and scrubbing your list against them before a campaign is a legal requirement in most markets. Honouring STOP/opt-out keywords is the SMS equivalent. See /answers/what-is-p2a-sms and /answers/gdpr-for-messaging.
What is A2P 10DLC?
A2P 10DLC (10-digit long code) is the US carrier framework that lets businesses send application-to-person SMS from standard 10-digit local numbers, provided the brand and each campaign are registered with The Campaign Registry (TCR). Registration unlocks sanctioned, higher throughput and better deliverability than an unregistered long code, which US carriers now filter or block. It sits between short codes and toll-free among US A2P options.
What is an alphanumeric sender ID?
An alphanumeric sender ID is a brand name of up to 11 letters and digits that appears instead of a phone number as the sender of an SMS. It makes a message instantly recognisable, but recipients cannot reply to it, and most regulated markets require each ID to be registered before operators will deliver it.
What is an SMS suppression list?
An SMS suppression list is a sender's own register of phone numbers that must not receive its marketing messages — people who replied STOP, withdrew consent or asked not to be contacted. Every promotional send is checked against it, so an opted-out number is never messaged again by mistake.
What is DLT registration in India?
DLT (Distributed Ledger Technology) registration is the mandatory Indian regime, set by TRAI, under which every commercial SMS sender, sender ID and message template must be registered on an operator-run blockchain platform before traffic will deliver. Unregistered or mismatched messages are blocked by the operator, not merely rate-limited.
What is double opt-in?
Double opt-in is a two-step consent process: after a user signs up for messages, you send a confirmation asking them to confirm the subscription (for example by replying YES), and only add them once they do. It produces the cleanest, most defensible consent — proving the number's owner genuinely wanted the messages — which protects both deliverability and compliance for marketing programs.
What is GSMA Open Gateway?
GSMA Open Gateway is the industry initiative — launched at MWC 2023 — for mobile network operators to expose network capabilities (number verification, location, device status, quality-on-demand) through a single set of standardised, CAMARA-defined APIs. It is the operator industry's answer to the fragmentation of CPaaS, RCS hubs, and per-operator interconnect.
What is on an SMS compliance checklist?
An SMS compliance programme rests on five pillars: obtain and record explicit opt-in, honour opt-out (STOP) immediately, register and correctly classify sender IDs, respect quiet hours and local marketing law, and protect personal data under the applicable privacy regime. Requirements differ by country, but these fundamentals apply almost everywhere and are what operators and regulators actually enforce.
What is STIR/SHAKEN?
STIR/SHAKEN is a framework of IETF and ATIS standards that cryptographically signs the calling number on a VoIP call so terminating carriers can verify the caller ID has not been spoofed. STIR (Secure Telephone Identity Revisited) defines the signed PASSporT token; SHAKEN (Signature-based Handling of Asserted information using toKENs) defines how carriers apply it. It is mandated for US and Canadian carriers to fight illegal caller-ID spoofing and robocalls. See /answers/what-is-cli and /answers/what-is-sender-id-spoofing.
What is TCPA compliance for SMS?
The Telephone Consumer Protection Act is the United States law governing calls and text messages to mobile numbers. For A2P senders it sets the consent standard, the opt-out obligation and the time-of-day restriction — and it carries statutory damages per message, which is why US messaging programmes are audited more carefully than most.
What is toll-free messaging?
Toll-free messaging is A2P SMS and MMS sent from a toll-free number — in North America the 800, 833, 844, 855, 866, 877, and 888 prefixes. Toll-free numbers must be verified with the carriers before they can send A2P at scale; once verified they offer high throughput and broad reach without the cost and lead time of a short code. It is a common alternative to 10DLC for higher-volume US traffic. See /answers/what-is-a2p-10dlc and /answers/what-is-short-code.
Operations & fraud57 terms
What goes wrong in production — grey routes, SIM-box fraud, SMS pumping (AIT), sender-ID spoofing, OTT bypass, hop-by-hop latency, route failover, A2P monetization for operators.
ASR — Answer-Seizure Ratio explained
ASR (Answer-Seizure Ratio) is the percentage of call attempts (seizures) that are answered by the called party. It is the single most important voice-quality KPI in carrier interconnect — operators, wholesale voice traders, and contact-centre platforms all live and die by their ASR per destination. ASR below the destination's normal range is an immediate red flag for routing degradation, fraud, or signalling issues.
ATG — Anti Traffic Generation in A2P firewalls
ATG (Anti Traffic Generation) is the umbrella term for the set of techniques an operator-side SMS firewall uses to detect and stop artificially-generated SMS traffic — pumped OTPs, SIM-box-originated A2P, bot-driven smishing campaigns, and the various flavours of grey-route abuse that look like organic traffic but aren't. ATG is what stands between the operator's revenue and the always-evolving fraud market.
EDR vs CDR — what's the difference?
CDR (Call Detail Record) is the operator's billing record for a single chargeable event — a call, an SMS, a data session — typically generated at the network element that mediated the event (MSC, SMSC, GGSN, OCS). EDR (Event Detail Record) is the broader analytics-and-application-layer record that captures everything happening around an event: not just the billed call, but the platform-level metadata that surrounds it. CDRs are what get billed; EDRs are what get analysed.
How do I activate my BroadNet account?
Request test access at /signup and a BroadNet engineer replies within one business day with test credentials; your first test message typically goes out about five minutes after you receive them. Test credentials work against the production endpoint, https://api.broadnet.me, and test messages go only to the mobile number you verify, so you can build and test end to end. To reach real recipients you complete business/KYC verification, which unlocks live sending and registered sender IDs, and add billing; production access is then switched on for your account, typically 5–15 business days from request to production. Going live is not a code change. See /developers/quickstart.
How do I build an OTP verification flow?
Build an OTP flow in five steps: generate a short single-use code server-side, send it over a high-priority channel with a fallback, store a hashed copy with a short expiry, verify the user's input against it with attempt limits, and rate-limit requests to defend against pumping. Keep the code out of logs, never trust the client to validate, and prefer network-based verification where it removes the code entirely.
How do I get an SMS short code?
A short code is a 4–6 digit number leased for high-volume two-way SMS, obtained by applying through a provider or the market's short-code registry, submitting your brand and use case for operator approval, and waiting through a provisioning and vetting period. Short codes offer high throughput and strong deliverability for campaigns and OTP, but they cost more and take longer to provision than a sender ID or long code.
How do I improve SMS delivery rates?
Improve SMS delivery rates by sending over direct operator routes, registering your alphanumeric sender IDs, cleaning recipient lists with HLR lookups, using correct GSM-7/Unicode encoding, and monitoring delivery receipts so you catch and re-route failures fast. Most chronic delivery problems trace back to two causes: grey routes that firewalls block, and unregistered sender IDs that operators drop before the message ever reaches a handset.
How do I rotate or revoke API keys?
In the dashboard, go to API keys, generate a new key, deploy it to your applications, then revoke the old key. Revocation is instant, and keys are never logged, so a rotated key stops working immediately with no residual exposure. Rotate on a schedule (for example quarterly) and immediately after any suspected exposure, and treat the token from your test credentials as a production secret: it calls the production endpoint. See /developers/authentication.
How do I scale SMS throughput?
Scale SMS throughput by binding over SMPP for sustained high volume, provisioning enough operator capacity ahead of demand, spreading load across multiple binds or routes, respecting rate limits with backoff, and validating lists first so you are not wasting capacity on undeliverable numbers. Peak bursts — like OTP at a product launch — need capacity reserved in advance, not requested live.
How do I send bulk SMS?
To send bulk SMS, connect to a provider over REST or SMPP (or upload a list to a campaign dashboard), register your sender ID, confirm every recipient has opted in, then send in throughput-managed batches while watching delivery receipts. The four things that determine success are a clean consented list, a registered sender ID, correct encoding to control segment count, and DLR monitoring so you catch failures early. See /products/bulk-sms.
How do I send international SMS?
To send SMS internationally, format every number in full E.164 form (a plus sign, country code, and national number), send through a provider with direct routes to your destination countries, register a sender ID where the market requires it, and account for per-country pricing and content rules. The hard part is not the API call — it is route quality and compliance, which vary sharply from one country to the next.
How do I test an SMS integration?
Test an SMS integration with your test credentials first: they work against the production endpoint, so send to your own verified number, confirm the API returns the expected accepted response, verify the delivery receipt (DLR) arrives via webhook, then check encoding, sender ID, and segment count before you go live. After approval, send a small first batch to your real destination countries to validate route quality, and only then scale.
How do you register a WhatsApp Business API number?
To register a number for the WhatsApp Business API you need a Meta business portfolio, a WhatsApp Business Account (WABA) inside it and a phone number you own that can receive an SMS or a voice call. You add the number to the WABA with a display name, verify it with the code Meta sends, set a two-step verification PIN and register it on the Cloud API. BroadNet, an official Meta Business Solution Provider, runs these steps with its customers.
How do you send an SMS via API?
Sending an SMS through an HTTP API means passing the destination number, sender ID, and message text to a REST endpoint that hands the message to operator networks and returns a message ID you can track for delivery.
How does Diameter signaling security work?
Diameter signaling security is the set of operator controls — a Diameter Edge Agent (DEA) and a signaling firewall applying GSMA FS.19 rules — that protect the 4G/LTE and 5G non-standalone Diameter control plane from location tracking, subscriber-data theft, and fraud. It screens S6a/S6d and roaming Diameter messages at the network edge so only legitimate inter-operator signaling reaches the HSS.
How does email deliverability work?
Email deliverability is the discipline of getting legitimate email into the inbox rather than the spam folder or a hard bounce. It rests on sender authentication (SPF, DKIM, DMARC), a warmed sending reputation tied to your IP and domain, clean list hygiene, and engagement signals mailbox providers watch. Authentication proves who sent the message; reputation and engagement decide where it lands.
How does SMS routing and least-cost routing (LCR) work?
SMS routing decides which operator path each message takes to reach a handset; least-cost routing (LCR) automatically selects the cheapest available route that still meets quality and compliance rules. Because every destination has multiple possible paths at different prices and reliabilities, good routing balances cost against deliverability — favouring direct operator routes and steering clear of grey routes that are cheap but unreliable.
How does SS7 and Diameter signaling security work?
SS7 signaling security is the set of operator controls — signaling firewalls, per-category message filtering, and peer reputation scoring — that protect the SS7 and Diameter control plane from location tracking, SMS interception, and fraud. Aligned to GSMA IR.82, IR.88, FS.07 and FS.11, it screens MAP and Diameter operations at the network edge so only legitimate inter-operator signaling passes.
How does telecom fraud prevention work?
Telecom fraud prevention is the layered defence operators and enterprises use against messaging and voice fraud — AIT/SMS pumping, grey routes, SIM-box bypass, smishing, sender-ID spoofing, and Wangiri call-back scams. It combines SMS and SS7/Diameter firewalls, real-time number intelligence, traffic analytics, and content screening to detect and block abuse at the moment it enters the network.
MAP-PSI — Provide-Subscriber-Info, and why it matters for SS7 security
MAP-PROVIDE-SUBSCRIBER-INFO (MAP-PSI) is an SS7 MAP operation that lets one network element query another for subscriber state — typically the serving MSC, the current location (Cell-ID and LAI), and the IMEI. It was designed for legitimate inter-operator uses (roaming partner queries, lawful intercept, network-internal services), but it became one of the canonical SS7 attack-surface operations and is now tightly controlled by SS7 signalling firewalls.
MAP-SRI-for-SM — Send-Routing-Info-for-SM, and SS7 SMS security
MAP-SEND-ROUTING-INFO-FOR-SM (MAP-SRI-for-SM) is the SS7 MAP operation an SMSC sends to a recipient's HLR to ask "where is this subscriber right now, and how do I deliver an SMS to them?" The response includes the IMSI and the serving MSC address — without which no cross-operator SMS can be delivered. It is also, historically, the single most-abused SS7 operation in the world, and the centrepiece of SS7 firewall policy.
MTTR — Mean Time To Recovery explained
MTTR (Mean Time To Recovery, sometimes Mean Time To Restore or Mean Time To Repair) is the average time from when a service incident begins to when normal service is restored. It is the single most actionable operational KPI on a telecom platform — every minute of MTTR reduction directly translates to fewer subscriber complaints, fewer SLA breach credits, and lower revenue loss during incidents.
What are SMS OTP best practices?
Deliver SMS one-time passwords over a dedicated high-priority route, keep codes short (4–8 digits), expire them quickly (typically 5–10 minutes), enforce single use, and rate-limit requests per number to defend against SMS-pumping fraud. Put the brand name and the code near the start of the message, include no clickable links (so the message can't be confused with phishing), and configure a fallback channel for when SMS is slow. See /products/otp.
What determines VoIP call quality?
VoIP call quality is decided by four network impairments — latency, jitter, packet loss, and the codec — summarised by a single Mean Opinion Score (MOS). Because voice is carried as RTP packets over IP, delayed, out-of-order, or dropped packets degrade the audio the listener hears. Managing these with QoS, jitter buffers, and the right codec is what keeps calls clear at scale.
What is a good SMS delivery rate?
A healthy A2P SMS delivery rate on direct routes is typically in the high-90s percent for clean, consented lists in well-supported markets, though the realistic ceiling varies by country, operator, and list quality. What matters more than a single benchmark is stability: direct routes deliver consistently, while grey routes may look high one week and collapse the next as firewalls catch them. Measure your own rate by country and operator over time.
What is a grey route in SMS?
A grey route is A2P SMS traffic that bypasses the destination operator's official A2P agreement and is delivered through a path priced for P2P or other consumer-class traffic — typically a SIM box, a foreign HLR backdoor, or an undeclared aggregator interconnect. Grey routes deliver messages cheaply but unreliably, undermine operator monetization, and are aggressively blocked by SMS firewalls.
What is a message queue in messaging?
A message queue holds submitted messages until they can be sent, smoothing bursts and respecting throughput limits. When you submit faster than the route allows, the platform queues the overflow and releases it at the permitted rate, so a spike does not overwhelm the operator or breach rate limits. Queue behaviour affects how quickly a large or bursty send actually goes out.
What is A2P monetization?
A2P monetization is the operator-side discipline of capturing wholesale revenue from application-to-person SMS traffic that would otherwise be delivered grey or peer-to-peer. It is one of the largest single SMS revenue streams for tier-1 operators globally — the A2P SMS market is worth USD 75-95 billion per year, and operators capture an increasing share through firewalls, direct agreements, and IR.71-aligned commercial frameworks.
What is ACD (Average Call Duration)?
ACD (Average Call Duration) is the mean length of answered calls over a period — total talk time divided by the number of answered calls. It is a core voice-traffic KPI: combined with call volume it gives the Erlang load used to size trunks and agents, and alongside ASR it reveals route and service quality. (Not to be confused with an Automatic Call Distributor.) Size capacity with the /tools/erlang-calculator. See /answers/what-is-asr and /answers/what-is-pdd.
What is AIT (Artificially Inflated Traffic)?
AIT (artificially inflated traffic) — also called SMS pumping or toll fraud — is a scheme where fraudsters use bots to trigger huge volumes of OTP or verification SMS to number ranges they control on a complicit operator, then collect a share of the termination fees. The victim is the business paying for the messages. Left unchecked, AIT can inflate an OTP bill many times over before anyone notices.
What is an MVNO?
An MVNO (mobile virtual network operator) is a mobile service provider that sells its own branded plans but does not own a radio network — it buys access to a host operator's network at wholesale rates. The MVNO owns the brand, the customer relationship and usually the billing, while the host network carries the calls, data and messages.
What is an SMS fallback strategy?
An SMS fallback strategy automatically re-sends a message via SMS when a richer channel — WhatsApp or RCS — fails to deliver or the recipient isn't reachable there, so the message still lands. It combines the branding, richness, and economics of modern channels with SMS's universal reach as the safety net, so you get the best of both without sacrificing deliverability. See /products/omnichannel.
What is an SMS firewall?
An SMS firewall is an operator platform that inspects, classifies, and controls SMS traffic on the messaging path. It blocks grey routes, SIM-box injection, smishing, and sender-ID spoofing while enforcing that application-to-person (A2P) traffic is properly declared and billed — protecting subscribers from fraud and recovering leaked A2P revenue.
What is CPS (Calls Per Second)?
CPS (calls per second) is the voice-network equivalent of messaging TPS: the maximum rate at which a platform or carrier trunk accepts new call attempts. It caps outbound dialing bursts — voice-OTP campaigns, notifications, or contact-center diallers — independently of how many calls are concurrently active. Exceeding the contracted CPS causes call attempts to be rejected or queued. See /answers/what-is-tps, /answers/what-is-pdd, and /tools/erlang-calculator.
What is hop-by-hop latency in SMS delivery?
Hop-by-hop latency is the cumulative delay added by each intermediate SMSC or aggregator between your application and the recipient's handset. A direct A2P route has 2-3 hops (app → BroadNet SMSC → operator SMSC → handset). A grey route can have 8-12 hops, each adding tens to hundreds of milliseconds of queue and signalling delay. For OTPs and time-sensitive messaging, hop count is the dominant cost.
What is IRSF (International Revenue Share Fraud)?
IRSF (International Revenue Share Fraud) is a telecom fraud in which criminals lease international premium-rate numbers and then generate artificial calls or messages to them, so the originating operator or business pays inflated termination fees while the fraudster and the number provider split the revenue.
What is jitter in VoIP?
Jitter is the variation in the arrival time of RTP voice packets. Packets sent at even intervals arrive unevenly because of network congestion and varying routes, and that unevenness garbles audio if played straight out. A jitter buffer holds incoming packets briefly and releases them at a steady rate to smooth playback — trading a little added delay for cleaner sound. Excessive jitter beyond the buffer's depth causes dropouts. See /answers/voip-quality, /answers/what-is-rtp, and /answers/what-is-mos.
What is LCR (Least-Cost Routing)?
LCR (Least-Cost Routing) automatically selects the cheapest available route for each message or call from a rate table of every path to a destination. Mature LCR weighs price against quality and compliance, not price alone — because the cheapest SMS path is often a grey route whose delivery is unreliable and whose sender IDs break. The right target is least effective cost: price per successfully delivered message. See /answers/sms-routing-lcr, /answers/what-is-grey-route-sms, and /operators/smsc-gateway.
What is MOS (Mean Opinion Score)?
MOS (Mean Opinion Score) is the standard measure of voice call quality, rated 1 (bad) to 5 (excellent). 4.0 and above is toll quality; below 3.5 is noticeably degraded. Originally a human listening test, MOS is now usually estimated automatically (per ITU-T models) from measured latency, jitter, and packet loss. It is the single number carriers use to compare routes and diagnose a poor call path. See /answers/voip-quality, /answers/what-is-jitter, and /products/voice.
What is NRTRDE (Near Real Time Roaming Data Exchange)?
NRTRDE (Near Real Time Roaming Data Exchange), defined in GSMA TD.35, requires a visited operator to send roaming usage records to the home operator within four hours of the event — far faster than the daily TAP file. Its purpose is fraud control: high-value roaming fraud such as SIM-box or premium-rate abuse can run up huge losses before a daily TAP cycle would surface it, so NRTRDE shortens the detection window. See /answers/what-is-tap and /answers/telecom-fraud-prevention.
What is OTP delivery rate?
OTP delivery rate is the share of one-time passcode messages that the destination operator confirms as delivered to the handset: delivered receipts divided by OTPs submitted, measured from delivery receipts (DLRs). It is not the same as the verification (conversion) rate, the share of users who actually enter the code, because a delivered code can still go unused. BroadNet's coverage pages give the typical operator-direct delivery rate for each market; on the UAE page it is 99.6%.
What is OTT bypass?
OTT bypass is the slow replacement of operator SMS revenue by Over-The-Top messaging apps (WhatsApp, Telegram, iMessage, Signal). Globally, P2P SMS traffic has declined ~30% since 2019 as users move conversational messaging to OTT. For operators, OTT bypass is the loss of the consumer messaging tariff. For enterprise senders, it is the rebalancing of channel mix toward WhatsApp and RCS.
What is PDD (Post-Dial Delay)?
PDD (Post-Dial Delay) is the time between the moment a call is initiated — a caller finishing dialing, or a system placing a call — and the moment ringing is heard or the call connects. High PDD, usually caused by long signaling paths or route-hunting across multiple carriers, makes callers hang up before connection and is a classic symptom of low-quality wholesale voice routes. See /answers/what-is-asr, /answers/what-is-acd, and /tools/erlang-calculator.
What is rate limiting in SMS?
Rate limiting caps how many messages or requests are accepted in a given time window — per API key, per sender, or per destination number — to protect throughput, enforce fair use, and defend against abuse such as SMS pumping. It is expressed as a rate (for example messages per second) and is what keeps one runaway job or one attacker from degrading delivery for everyone.
What is route failover in messaging?
Route failover is the automatic re-routing of an SMS submission from a failing primary route to a healthy secondary route, ideally within the same submit_sm transaction. For a CPaaS handling tens of millions of messages a day, failover is the difference between a 99.9% delivery rate and a 99.05% rate — a tenfold difference in user-visible failures.
What is sender ID spoofing?
Sender ID spoofing is sending an SMS with a falsified originator — appearing as `BANK-OF-X`, `DHL`, `MyBrand` when the sender has no authorisation to use that string. It is the SMS equivalent of email phishing, and it is the dominant vector for smishing attacks globally. The protocol weakness: GSM SMS has no end-to-end sender authentication, so the SMSC accepts whatever sender ID the originating ESME submits.
What is SIM box fraud?
A SIM box is a piece of hardware that holds dozens or hundreds of physical SIM cards from a mobile operator and uses them to terminate inbound international calls (or A2P SMS) as if they originated on-net from individual consumer subscribers. It bypasses the operator's international termination tariff and the A2P SMS tariff, costing operators globally an estimated USD 3-7 billion per year.
What is SIM swap fraud?
SIM swap fraud is an attack where a criminal persuades or bribes a mobile operator to move a victim's number onto a SIM the attacker controls. Every SMS one-time passcode for that number then arrives on the attacker's handset, which is why SMS OTP alone is not sufficient authentication for a high-value action.
What is smart routing in SMS?
Smart routing is the logic a messaging platform uses to choose the best path for each message in real time — selecting among operator routes by quality, cost, and destination, and re-routing automatically when a path degrades. It aims to maximize delivery and control cost without manual intervention, and is closely related to least-cost routing and automatic route failover.
What is smishing?
Smishing (SMS phishing) is a fraud technique where attackers send SMS impersonating banks, government agencies, or delivery services to trick recipients into clicking malicious links, revealing credentials, or paying fake fees. Because people are conditioned to trust and act quickly on SMS from brands, smishing is highly effective. Defence is layered: operator SMS firewalls, sender-ID registration and anti-spoofing, URL reputation, and subscriber education.
What is SMS analytics?
SMS analytics is the measurement of messaging performance — delivery rate, failure reasons by operator, click-through on links, inbound replies, opt-outs, and ultimately conversion and ROI. Because SMS has no native open rate, analytics is built from delivery receipts, tracked links, and downstream conversions. Good analytics turns sending into a feedback loop you can optimize.
What is SMS pumping / artificial inflated traffic (AIT)?
Artificially Inflated Traffic (AIT) — also called SMS pumping or SMS toll fraud — is a scam in which bots trigger huge volumes of one-time-passcode and verification SMS from a brand's own app or website. The messages never reach real users; fraudsters colluding in the delivery chain simply collect the per-message termination fees. You pay the SMS bill; they take the cut.
What is SMS scheduling?
SMS scheduling is sending a message at a specified future time rather than immediately — used to reach recipients during their local business hours, coordinate campaigns, and time reminders. Good scheduling is timezone-aware and respects quiet hours, so a message meant for 10am arrives at 10am for each recipient, not all at once in one timezone.
What is the best channel for OTP delivery?
SMS is the default OTP channel because it reaches every phone with no app, but the best choice depends on the market and risk profile: SMS for universal reach, flash call for lower cost and speed where supported, WhatsApp for app-engaged users, silent network authentication for frictionless verification, and voice as a fallback. The strongest verification flows don't pick one — they cascade through several so a failed channel never blocks a login. See /products/otp.
What is TPS (Transactions Per Second)?
TPS (transactions per second) — also called MPS or send rate — is the throughput ceiling of a messaging bind or account: how many SMS submit_sm PDUs the SMSC accepts per second before it returns throttling errors. A2P binds are provisioned at a contracted TPS; exceeding it triggers ESME_RTHROTTLED responses. TPS, not raw volume, determines how fast a campaign or OTP burst clears. See /answers/what-is-throughput-sla, /answers/what-is-cps, and /tools/smpp-error-codes.
What is Wangiri fraud?
Wangiri (Japanese for 'one ring and cut') is a voice fraud in which scammers place brief missed calls from premium-rate international numbers, hoping victims call back and get charged high per-minute fees the fraudster shares in. An SMS variant lures the call-back with a text. Defences include call-pattern analytics, premium-rate destination blocking, and subscriber education. See /answers/telecom-fraud-prevention and /answers/what-is-cli.
Why are my SMS messages not being delivered?
Undelivered SMS almost always trace to one of a few causes — an unregistered sender ID, an invalid or unreachable number, grey-route filtering, wrong encoding, or a handset that is off — and each shows up differently in the delivery receipt.
Commercial & buying46 terms
Pricing models, throughput SLAs, per-message pricing for WhatsApp, omnichannel orchestration, moving from test access to production, what a CPaaS is and isn't.
CPaaS vs UCaaS — what's the difference?
CPaaS (Communications Platform as a Service) and UCaaS (Unified Communications as a Service) are both cloud communications, but serve opposite jobs: CPaaS gives developers APIs to embed messaging, voice, and video inside their own apps and workflows, while UCaaS is a ready-made suite — business phone, video meetings, and team chat — for a company's employees. CPaaS is building blocks; UCaaS is a finished product.
How can I reduce OTP costs?
Reduce OTP costs by sending fewer, cheaper, and more successful codes: prefer network-based verification (silent network authentication) that sends no billable message where supported, rate-limit to stop SMS pumping inflating volume, keep OTP messages to one GSM-7 segment, route over direct paths so codes are not re-sent, and use cheaper channels like flash call where they fit. The biggest saving is usually eliminating fraudulent and failed sends, not shaving the unit rate.
How can I reduce SMS costs?
Reduce SMS costs by attacking both the price per message and the number of wasted messages: keep messages inside one segment, stay on GSM-7 encoding, validate numbers before sending so you don't pay to text dead or wrong-country numbers, route over direct agreements to avoid re-sends, register sender IDs so firewalls don't silently drop traffic, and move rich or high-volume flows to the channel with the best economics. The largest saving is usually eliminating failed and duplicate sends, not shaving the unit rate.
How do I choose a CPaaS provider?
Evaluate a CPaaS provider on six dimensions: channel breadth (SMS, WhatsApp, RCS, voice and email behind one API), route ownership, developer experience (SDKs, test access before you sign, honest docs), reliability SLA, regional depth and compliance, and the support model. A true CPaaS unifies every channel behind one API and one contract instead of forcing a separate integration per channel. BroadNet has operated as a MENA-native CPaaS since 2003, with omnichannel APIs over directly owned carrier routes — see /products/omnichannel.
How do I choose an SMS provider?
Choose an SMS provider on five measurable criteria: route quality (direct operator agreements versus grey routes), geographic coverage, deliverability transparency (real-time delivery receipts with operator-level error codes), throughput and uptime SLA, and compliance support (sender-ID registration, data residency). Price matters, but the cheapest per-message rate is usually a grey route that costs more per delivered message. BroadNet runs A2P to 200+ countries — direct to the operator in 86, over 1,000+ direct operator connections — at a 99.99% platform SLA — see /operators.
How do I download invoices and statements?
In the dashboard, go to Billing → Invoices and download any invoice as a PDF. Monthly statements are itemised by channel and destination country so you can see exactly where spend went. For UAE accounts, invoices are VAT-compliant and show your TRN (Tax Registration Number).
How do I migrate to a new SMS provider?
Migrate to a new SMS provider by running the new route in parallel with your current one, re-registering sender IDs in each market, updating API or SMPP credentials and webhook endpoints, testing delivery on real destinations, then shifting traffic gradually while watching delivery receipts. A phased cutover — not a hard switch — protects deliverability and lets you compare cost per delivered message before you fully commit.
How do I top up my balance?
BroadNet prepaid accounts run on a balance you top up in advance. In the dashboard, go to Billing → add funds to top up by card or bank transfer. Set an auto-recharge threshold so your balance refills automatically and sending never pauses mid-campaign. Enterprise accounts can instead use monthly invoicing with agreed credit terms rather than pre-funding a balance.
How do you measure SMS marketing ROI?
Measure SMS marketing ROI by attributing revenue driven by a campaign against its full cost — message spend plus incentives — using unique links, promo codes, or holdout groups to isolate the SMS effect. Because SMS is read almost universally within minutes, well-targeted, consented campaigns typically show strong returns, but the honest number depends on attribution discipline and list quality, not on open rates alone.
How do you use SMS for abandoned-cart recovery?
Abandoned-cart SMS re-engages shoppers who left items in their basket with a short, timely reminder — often with a product image via RCS or WhatsApp, and sometimes an incentive — recovering revenue that would otherwise be lost. Because it is a marketing message, it requires explicit opt-in and DNC/quiet-hours compliance. It is one of the highest-ROI messaging use cases in e-commerce; see /solutions/ecommerce-retail.
How do you use SMS for appointment reminders?
SMS appointment reminders cut no-shows by delivering a timely, high-open-rate reminder with the date, time and location, plus a reply-to-confirm or reply-to-reschedule option using two-way SMS. Because SMS needs no app and is read within minutes, it reaches patients and customers that email and app notifications miss — which is why clinics, healthcare providers, salons and service businesses rely on it. See /products/two-way-sms.
How do you use SMS for delivery notifications?
SMS delivery notifications keep customers informed at each fulfilment milestone — order confirmed, shipped, out for delivery, delivered — with an optional tracking link and a reply channel to reschedule. SMS is ideal for logistics updates because it is read within minutes and needs no app install, so time-sensitive 'your driver is 10 minutes away' messages actually get seen. Common across e-commerce, retail and logistics; see /solutions/ecommerce-retail.
How do you use SMS for payment and transaction alerts?
SMS payment and transaction alerts notify customers in real time about debits, credits, low balances, and suspected fraud — a core requirement for banks, fintechs and payment providers. These messages must be fast, reliable and sent over direct routes with a strong SLA, classified as transactional (never marketing), and free of sensitive data such as full card numbers. See /solutions/banking-finance.
How do you use WhatsApp for customer support?
WhatsApp Business API turns WhatsApp into a scalable support channel: customers message your verified business number, and within the 24-hour service window your agents (and bots) can reply freely with text, images, documents, and quick-reply buttons. It suits asynchronous, media-rich support at scale, with automation handling routine questions and smooth handoff to human agents for the rest. See /products/whatsapp-business-api.
How does A2P messaging monetization work?
Messaging monetization is how a mobile operator captures the revenue in application-to-person traffic — deploying an SMS firewall to force grey-route traffic onto paid A2P routes, running a sender-ID registry so only licensed brands can send, and billing A2P at its true wholesale value.
How does number masking protect user privacy?
Number masking (number anonymization) connects two people — a rider and driver, a buyer and courier, a patient and clinician — through a temporary proxy number, so neither party ever sees the other's real phone number. It protects personal privacy, keeps the communication on your platform, and gives you a controllable, auditable channel for calls and SMS. See /answers/what-is-number-masking.
How does omnichannel messaging work?
Omnichannel messaging reaches a customer across SMS, WhatsApp, RCS, voice, and email through one API and one conversation thread — automatically choosing or failing over between channels by reach, cost, and delivery result. Instead of integrating each channel separately, a business sends to a customer and the platform selects the best route, so the conversation stays continuous no matter which channel actually delivers.
How much does A2P SMS cost?
A2P SMS is priced per message segment (an MT, or mobile-terminated message), and the rate varies by destination country and operator — from fractions of a cent in some markets to several cents in others, driven mostly by the operator's A2P termination fee. Long messages are split into 160-character (GSM-7) or 70-character (Unicode/UCS-2) segments, and every segment is billed separately. For country-by-country rates see /pricing/sms, and estimate segment counts with /tools/sms-segment-calculator.
SMS pricing per MT — what you're actually paying for
An SMS price quote is almost always "per MT," meaning per mobile-terminated message — per message arriving at a handset. The headline number is the unit you pay for, but the full cost of an SMS programme includes setup fees, sender-ID fees, minimum commitments, surge pricing during peak hours, and the carrier-specific tariff for the destination operator.
SMS vs email marketing — how do they compare?
SMS delivers far higher open and read rates than email — industry studies consistently report SMS open rates around 98%, most within minutes — making it ideal for time-sensitive, short, high-urgency messages. Email carries richer content, images and long-form copy at a lower cost per message, making it better for newsletters, detailed offers and content. They are complementary: use SMS for immediacy and email for depth, and coordinate both in one omnichannel program. See /products/omnichannel.
SMS vs push notifications — how do they compare?
SMS reaches any mobile number on any phone with no app and is read within minutes, making it ideal for critical, universal messages like OTP and alerts; push notifications are free to send but only reach users who installed your app and granted permission, and are easily muted or ignored. Use SMS for reach and reliability, push for engaged in-app users, and combine them so a missed push can fall back to SMS.
SMS vs WhatsApp for business — which should you use?
Use SMS when you need universal reach and instant delivery with no app or opt-in dependency — OTPs, transaction alerts, and any message that must reach every phone. Use WhatsApp when you want a branded, verified sender, rich media, and two-way conversation — marketing, support, and richer notifications — accepting that it requires the app, an opt-in, and template approval. The strongest programs use both behind one omnichannel API, choosing per message. See /products/omnichannel.
Test credentials vs production: what changes when you go live?
BroadNet does not run a separate sandbox. Your test credentials work against the production endpoint, https://api.broadnet.me, with the same API and the same code you will run in production; test messages go only to your own verified number(s), and their delivery receipts come back to your webhook. Production access and routes are switched on for your account after approval (sender identity, traffic purpose and sender IDs), typically 5–15 business days from request, and your code does not change.
What are SMS marketing best practices?
Effective SMS marketing rests on permission and restraint: message only opted-in recipients, identify your brand, lead with clear value, keep it to one idea and one call to action, respect quiet hours and frequency limits, and always offer an easy opt-out. Because SMS is read within minutes by nearly everyone, the channel rewards relevance and punishes over-sending. See /products/bulk-sms and /solutions/ecommerce-retail.
What are the WhatsApp message categories?
WhatsApp Business Platform messages fall into four categories that Meta uses for its rules and its pricing: Marketing, Utility and Authentication, which are pre-approved templates, and Service, the free-form replies a business sends inside the 24-hour customer service window. Each delivered message is billed by category and market, and from 1 October 2026 service replies are billed after a free tier of 1,000 service messages per business phone number per month. BroadNet, an official Meta Business Solution Provider, helps customers choose and submit the right category for each template.
What currencies and payment methods does BroadNet support?
BroadNet bills in AED and SAR for MENA accounts and in USD for international accounts. You can pay by major credit and debit card or by bank transfer, and enterprise accounts can arrange invoicing with agreed net credit terms instead of pre-funding a balance.
What is a broadcast list?
A broadcast list is a saved group of recipients you can message together — the audience for a bulk send or campaign. Unlike a group chat, recipients receive the message individually and do not see each other. A well-managed broadcast list is consented, segmented, and kept clean with validation and opt-out suppression, so each send reaches real, willing recipients.
What is a chatbot for business messaging?
A messaging chatbot is an automated agent that holds two-way conversations with customers on channels like WhatsApp, RCS, and SMS — answering FAQs, checking order status, capturing leads, and triaging support around the clock. It can be rule-based (following scripted flows) or AI-powered (understanding natural language), and the best implementations hand off to a human agent when the conversation needs one.
What is a cloud contact center (CCaaS)?
A cloud contact center, or CCaaS (Contact Center as a Service), is a hosted platform that runs customer-service voice and digital interactions — inbound and outbound calls, IVR, skills-based routing, agent desktops, and analytics — delivered over the internet instead of on-premise hardware. It combines telephony (often over a voice API and SIP trunking) with channel and workforce tooling into one agent-facing application.
What is a customer engagement platform?
A customer engagement platform (CEP) is software that orchestrates communication with customers across channels — SMS, WhatsApp, RCS, voice, email, push — often adding segmentation, journeys, automation, and analytics on top of the messaging layer. Where a CPaaS provides the channels and APIs, a CEP adds the campaign, journey, and data tooling to run engagement programs on them.
What is a direct operator connection?
A direct operator connection is an interconnect in which a messaging provider binds straight to a mobile operator's SMSC or A2P gateway under its own contract with that operator, instead of handing traffic to another aggregator. Each message takes one hop to the network that delivers it, which keeps latency, delivery receipts and pricing transparent.
What is a throughput SLA?
A throughput SLA is the contractually guaranteed sustained rate at which an aggregator will accept your submissions and deliver them to the operator — typically expressed in messages per second (MPS) or transactions per second (TPS). For OTP services, marketing-burst campaigns, and operator-grade integrations, throughput SLA is often more important than the unit price.
What is an SMS blast?
An SMS blast is a single message sent to a large list of recipients at once — a broad announcement, alert, or promotion. It is the simplest form of bulk messaging, but 'blast' also carries a warning: sending the same message to everyone regardless of consent, segment, or timing wastes spend and hurts deliverability. Effective bulk sending is targeted and consented, not indiscriminate.
What is an SMS keyword campaign?
An SMS keyword campaign invites people to text a keyword (like JOIN or SALE) to a short code or number to opt in, get information, or enter a promotion. The inbound keyword triggers an automated response and adds the sender to a consented list. It is a clean, self-service way to collect opt-in and run interactive promotions, and it depends on two-way messaging and a number that can receive replies.
What is an SMS survey?
An SMS survey collects feedback by text — sending a question and capturing the recipient's reply through two-way messaging. Because SMS is read within minutes by nearly everyone, response rates are high and fast, which makes it strong for short pulse surveys, NPS scores, and post-interaction feedback. It needs a number that can receive replies and a webhook to route responses into your system.
What is conversation pricing for WhatsApp?
Conversation pricing was Meta's billing model for the WhatsApp Business API until 1 July 2025: you paid per 24-hour conversation window with a user. Since then Meta bills per delivered template message — Marketing, Utility or Authentication — by category and country. From 1 October 2026 Meta bills replies inside the 24-hour customer service window per message, at the same rate as utility and authentication messages in that market: service replies after a free tier of 1,000 service messages per business phone number per month, utility templates from the first message.
What is conversational AI in messaging?
Conversational AI is software that understands and responds to natural-language messages, letting businesses automate two-way conversations across SMS, WhatsApp, RCS, and voice. In messaging it powers chatbots and virtual agents that answer questions, complete tasks, and escalate to humans with context — handling routine volume 24/7 while keeping the option of a person when the conversation needs one.
What is conversational commerce?
Conversational commerce is buying, selling, and supporting customers through messaging channels — WhatsApp, RCS, SMS, and chat — so product discovery, questions, checkout, and after-sales all happen in one continuous thread. It has grown quickly because customers increasingly prefer messaging a business over calling or navigating a website, and messaging's high open rates make it a reliable place to reach them. See /products/omnichannel.
What is CPaaS, and how does it work?
CPaaS (Communications Platform as a Service) is cloud software that exposes voice, SMS, WhatsApp, RCS, email, and verification as developer APIs — so a business can add communications to its own apps without contracting mobile operators directly. BroadNet is a MENA-native CPaaS operating since 2003, reaching 200+ countries over 1,000+ operator connections and carrying 300M+ messages a day.
What is CPaaS?
CPaaS — Communications Platform as a Service — is cloud software that exposes SMS, voice, WhatsApp, RCS, email, and verification as developer APIs, so a business can build customer communications into its own apps without contracting mobile operators directly. It turns multi-operator telecom plumbing — SMSCs, SS7, sender-ID registration, routing and failover — into a few authenticated API calls. BroadNet has run a MENA-native CPaaS since 2003, reaching 200+ countries over 1,000+ direct operator connections, with direct binds in 86 of them.
What is message personalization?
Message personalization tailors each message to the individual recipient — inserting their name, order, appointment, or other data through template variables — so a single campaign produces thousands of relevant, individual messages. Done well it lifts engagement and conversion; done carelessly it leaks a literal {{name}} to customers or, worse, the wrong person's data. Preview and validate templates before sending.
What is omnichannel messaging?
Omnichannel messaging is the orchestration of multiple messaging channels (SMS, WhatsApp, RCS, email, push, voice) as a single coherent customer journey, where channel choice is selected per message based on reachability, cost, urgency, and user preference — rather than being hard-coded per use case.
What is omnichannel orchestration?
Omnichannel orchestration is the logic that decides, per message and per recipient, which channel to use and in what order — sending on the best eligible channel (WhatsApp, RCS, SMS, voice, email) and falling back automatically when one is unavailable or undelivered. It turns a set of separate channels into a single intelligent delivery layer that maximizes reach, richness, and cost-efficiency at once.
What is promotional SMS?
Promotional SMS is marketing sent by SMS — offers, campaigns, announcements, abandoned-cart nudges. Unlike transactional messages, it requires explicit marketing opt-in, must honour opt-out (STOP) and quiet hours, and is often registered and routed as a distinct traffic class. Done well on consented lists it converts strongly; sent without consent it wastes spend and damages sender reputation.
What is SMS marketing automation?
SMS marketing automation triggers text messages automatically based on customer behaviour, events, or a schedule — a welcome message on signup, a cart-abandonment nudge, a birthday offer, a re-engagement series — rather than sending each campaign by hand. It combines audience data, triggers, and templates so the right message goes to the right person at the right moment, at scale, on consented lists.
What is TAP (Transferred Account Procedure)?
TAP (Transferred Account Procedure) is the GSMA standard file format — TAP3, defined in GSMA TD.57 — that a visited operator uses to send records of a roamer's calls, messages, and data usage back to their home operator for inter-operator billing settlement. TAP files are exchanged through data clearing houses, usually daily. Its near-real-time companion, NRTRDE, exists to catch roaming fraud faster than a daily TAP cycle allows. See /answers/what-is-nrtrde and /answers/edr-vs-cdr.
Most-read this quarter
The questions everyone asks first.
Ordered by traffic across our knowledge base — the foundational answers that come up in almost every conversation about business messaging.
- 01
What is A2P SMS?
A2P (application-to-person) SMS is a text message initiated by a business software application — for OTPs, notifications, alerts, transactional confirmations, marketing — delivered to a consumer mobile phone. A2P is the dominant business-messaging modality globally, with over 2 trillion A2P messages sent per year.
- 02
How do I choose an SMS provider?
Choose an SMS provider on five measurable criteria: route quality (direct operator agreements versus grey routes), geographic coverage, deliverability transparency (real-time delivery receipts with operator-level error codes), throughput and uptime SLA, and compliance support (sender-ID registration, data residency). Price matters, but the cheapest per-message rate is usually a grey route that costs more per delivered message. BroadNet runs A2P to 200+ countries — direct to the operator in 86, over 1,000+ direct operator connections — at a 99.99% platform SLA — see /operators.
- 03
How much does A2P SMS cost?
A2P SMS is priced per message segment (an MT, or mobile-terminated message), and the rate varies by destination country and operator — from fractions of a cent in some markets to several cents in others, driven mostly by the operator's A2P termination fee. Long messages are split into 160-character (GSM-7) or 70-character (Unicode/UCS-2) segments, and every segment is billed separately. For country-by-country rates see /pricing/sms, and estimate segment counts with /tools/sms-segment-calculator.
- 04
The WhatsApp 24-hour window explained
When a customer messages your WhatsApp Business number, you can reply freely with Service-category messages for the next 24 hours; from 1 October 2026 Meta bills service replies per message after a free tier of 1,000 service messages per business phone number per month. After the 24-hour window closes, you must use a pre-approved template (a Marketing, Utility or Authentication message, billed per delivered message) to re-initiate.
- 05
What is RCS?
RCS (Rich Communication Services) is the modern replacement for SMS — a protocol that supports verified branded senders, rich cards, suggested replies, read receipts, and group messaging. RCS Business Messaging (RBM) is the enterprise variant. Native in Android Messages since 2019; supported on iPhone since iOS 18 (2024).
- 06
SMS vs WhatsApp for business — which should you use?
Use SMS when you need universal reach and instant delivery with no app or opt-in dependency — OTPs, transaction alerts, and any message that must reach every phone. Use WhatsApp when you want a branded, verified sender, rich media, and two-way conversation — marketing, support, and richer notifications — accepting that it requires the app, an opt-in, and template approval. The strongest programs use both behind one omnichannel API, choosing per message. See /products/omnichannel.
- 07
What is a WhatsApp BSP?
A WhatsApp Business Solution Provider (BSP) is a Meta-approved partner that hosts enterprise access to the WhatsApp Business API. Businesses can also connect directly through Meta's Cloud API, but most work through a BSP for onboarding, template approval, verification, billing and support. BroadNet is an official Meta BSP.
- 08
What is SMPP?
SMPP (Short Message Peer-to-Peer) is the open-protocol standard for exchanging SMS between SMSCs, ESMEs (External Short Message Entities), and aggregators. Version 3.4 is the most widely deployed; 5.0 adds Unicode-clean headers. BroadNet supports both via plain TCP and TLS.
- 09
What is a grey route in SMS?
A grey route is A2P SMS traffic that bypasses the destination operator's official A2P agreement and is delivered through a path priced for P2P or other consumer-class traffic — typically a SIM box, a foreign HLR backdoor, or an undeclared aggregator interconnect. Grey routes deliver messages cheaply but unreliably, undermine operator monetization, and are aggressively blocked by SMS firewalls.
- 10
What is OTP?
OTP (One-Time Password) is a single-use code sent to a user to verify their identity for login, transaction, or account recovery. OTPs are most commonly delivered via SMS, but also via WhatsApp, email, voice, and authenticator apps. OTP is the most common form of 2FA (two-factor authentication) globally.
Reviewed quarterlySourced from real support ticketsPlain-text, no marketing copy
Can't find it?
Talk to support. A human picks up.
Every BroadNet account, from test access onward, gets direct access to the platform team. No tiers, no chatbot triage, no scripted replies — just engineers who run the routes you're sending on.
- support@broadnet.meEmail · reply within one business day
- broadnet.me/statusComponent status, incidents and the 99.99% SLA
- /developersAPI reference, TypeScript SDK and integration guides
Test access · reply within one business day
Reading is good. Sending is better.
Once the concepts make sense, the fastest way to lock them in is to send a real message. Request test access and try every channel you just read about on your own verified number.
$ npm install @broadnet/cpaas-sdk axios